dt-bindings: consolidate USB PHYs in bindings/phy

Move USB PHY bindings under usb directory to phy directory which already
contains other USB PHY bindings.

The Samsung USB PHY binding is obsolete and can be removed.
Signed-off-by: Rob Herring <robh@kernel.org>
Cc: Pawel Moll <pawel.moll@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ian Campbell <ijc+devicetree@hellion.org.uk>
Cc: Kumar Gala <galak@codeaurora.org>

Documentation/devicetree/bindings/usb/samsung-usbphy.txt

-SAMSUNG USB-PHY controllers
-
-** Samsung's usb 2.0 phy transceiver
-
-The Samsung's usb 2.0 phy transceiver is used for controlling
-usb 2.0 phy for s3c-hsotg as well as ehci-s5p and ohci-exynos
-usb controllers across Samsung SOCs.
-TODO: Adding the PHY binding with controller(s) according to the under
-development generic PHY driver.
-
-Required properties:
-
-Exynos4210:
-- compatible : should be "samsung,exynos4210-usb2phy"
-- reg : base physical address of the phy registers and length of memory mapped
-	region.
-- clocks: Clock IDs array as required by the controller.
-- clock-names: names of clock correseponding IDs clock property as requested
-	       by the controller driver.
-
-Exynos5250:
-- compatible : should be "samsung,exynos5250-usb2phy"
-- reg : base physical address of the phy registers and length of memory mapped
-	region.
-
-Optional properties:
-- #address-cells: should be '1' when usbphy node has a child node with 'reg'
-		  property.
-- #size-cells: should be '1' when usbphy node has a child node with 'reg'
-	       property.
-- ranges: allows valid translation between child's address space and parent's
-	  address space.
-
-- The child node 'usbphy-sys' to the node 'usbphy' is for the system controller
-  interface for usb-phy. It should provide the following information required by
-  usb-phy controller to control phy.
-  - reg : base physical address of PHY_CONTROL registers.
-	  The size of this register is the total sum of size of all PHY_CONTROL
-	  registers that the SoC has. For example, the size will be
-	  '0x4' in case we have only one PHY_CONTROL register (e.g.
-	  OTHERS register in S3C64XX or USB_PHY_CONTROL register in S5PV210)
-	  and, '0x8' in case we have two PHY_CONTROL registers (e.g.
-	  USBDEVICE_PHY_CONTROL and USBHOST_PHY_CONTROL registers in exynos4x).
-	  and so on.
-
-Example:
- - Exynos4210
-
-	usbphy@125B0000 {
-		#address-cells = <1>;
-		#size-cells = <1>;
-		compatible = "samsung,exynos4210-usb2phy";
-		reg = <0x125B0000 0x100>;
-		ranges;
-
-		clocks = <&clock 2>, <&clock 305>;
-		clock-names = "xusbxti", "otg";
-
-		usbphy-sys {
-			/* USB device and host PHY_CONTROL registers */
-			reg = <0x10020704 0x8>;
-		};
-	};
-
-
-** Samsung's usb 3.0 phy transceiver
-
-Starting exynso5250, Samsung's SoC have usb 3.0 phy transceiver
-which is used for controlling usb 3.0 phy for dwc3-exynos usb 3.0
-controllers across Samsung SOCs.
-
-Required properties:
-
-Exynos5250:
-- compatible : should be "samsung,exynos5250-usb3phy"
-- reg : base physical address of the phy registers and length of memory mapped
-	region.
-- clocks: Clock IDs array as required by the controller.
-- clock-names: names of clocks correseponding to IDs in the clock property
-	       as requested by the controller driver.
-
-Optional properties:
-- #address-cells: should be '1' when usbphy node has a child node with 'reg'
-		  property.
-- #size-cells: should be '1' when usbphy node has a child node with 'reg'
-	       property.
-- ranges: allows valid translation between child's address space and parent's
-	  address space.
-
-- The child node 'usbphy-sys' to the node 'usbphy' is for the system controller
-  interface for usb-phy. It should provide the following information required by
-  usb-phy controller to control phy.
-  - reg : base physical address of PHY_CONTROL registers.
-	  The size of this register is the total sum of size of all PHY_CONTROL
-	  registers that the SoC has. For example, the size will be
-	  '0x4' in case we have only one PHY_CONTROL register (e.g.
-	  OTHERS register in S3C64XX or USB_PHY_CONTROL register in S5PV210)
-	  and, '0x8' in case we have two PHY_CONTROL registers (e.g.
-	  USBDEVICE_PHY_CONTROL and USBHOST_PHY_CONTROL registers in exynos4x).
-	  and so on.
-
-Example:
-	usbphy@12100000 {
-		compatible = "samsung,exynos5250-usb3phy";
-		reg = <0x12100000 0x100>;
-		#address-cells = <1>;
-		#size-cells = <1>;
-		ranges;
-
-		clocks = <&clock 1>, <&clock 286>;
-		clock-names = "ext_xtal", "usbdrd30";
-
-		usbphy-sys {
-			/* USB device and host PHY_CONTROL registers */
-			reg = <0x10040704 0x8>;
-		};
-	};