ARM: dts: dra7: Fix bus_dma_limit for PCIe

Even though commit cfb5d65f ("ARM: dts: dra7: Add bus_dma_limit
for L3 bus") added bus_dma_limit for L3 bus, the PCIe controller
gets incorrect value of bus_dma_limit.

Fix it by adding empty dma-ranges property to axi@0 and axi@1
(parent device tree node of PCIe controller).

Cc: stable@kernel.org
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/dra7.dtsi

@@ -172,6 +172,7 @@ axi@0 {
 			#address-cells = <1>;
 			ranges = <0x51000000 0x51000000 0x3000
 				  0x0	     0x20000000 0x10000000>;
+			dma-ranges;
 			/**
 			 * To enable PCI endpoint mode, disable the pcie1_rc
 			 * node and enable pcie1_ep mode.
@@ -185,7 +186,6 @@ pcie1_rc: pcie@51000000 {
 				device_type = "pci";
 				ranges = <0x81000000 0 0          0x03000 0 0x00010000
 					  0x82000000 0 0x20013000 0x13000 0 0xffed000>;
-				dma-ranges = <0x02000000 0x0 0x00000000 0x00000000 0x1 0x00000000>;
 				bus-range = <0x00 0xff>;
 				#interrupt-cells = <1>;
 				num-lanes = <1>;
@@ -230,6 +230,7 @@ axi@1 {
 			#address-cells = <1>;
 			ranges = <0x51800000 0x51800000 0x3000
 				  0x0	     0x30000000 0x10000000>;
+			dma-ranges;
 			status = "disabled";
 			pcie2_rc: pcie@51800000 {
 				reg = <0x51800000 0x2000>, <0x51802000 0x14c>, <0x1000 0x2000>;
@@ -240,7 +241,6 @@ pcie2_rc: pcie@51800000 {
 				device_type = "pci";
 				ranges = <0x81000000 0 0          0x03000 0 0x00010000
 					  0x82000000 0 0x30013000 0x13000 0 0xffed000>;
-				dma-ranges = <0x02000000 0x0 0x00000000 0x00000000 0x1 0x00000000>;
 				bus-range = <0x00 0xff>;
 				#interrupt-cells = <1>;
 				num-lanes = <1>;