ARM: dts: Drop custom hwmod property for am4 uart

We can now probe devices with ti-sysc interconnect driver and dts
data. Let's drop the custom ti,hwmods dts property. We have already
dropped the platform data earlier, but have been still allocating it
dynamically, which is no longer needed.

Cc: Keerthy <j-keerthy@ti.com>
Tested-by: Keerthy <j-keerthy@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/boot/dts/am437x-l4.dtsi

@@ -166,7 +166,6 @@ gpio0: gpio@0 {
 
 		target-module@9000 {			/* 0x44e09000, ap 16 04.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart1";
 			reg = <0x9050 0x4>,
 			      <0x9054 0x4>,
 			      <0x9058 0x4>;
@@ -678,7 +677,6 @@ target-module@8000 {			/* 0x48008000, ap 6 10.0 */
 
 		target-module@22000 {			/* 0x48022000, ap 8 0a.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart2";
 			reg = <0x22050 0x4>,
 			      <0x22054 0x4>,
 			      <0x22058 0x4>;
@@ -707,7 +705,6 @@ uart1: serial@0 {
 
 		target-module@24000 {			/* 0x48024000, ap 10 1c.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart3";
 			reg = <0x24050 0x4>,
 			      <0x24054 0x4>,
 			      <0x24058 0x4>;
@@ -1385,7 +1382,6 @@ spi3: spi@0 {
 
 		target-module@a6000 {			/* 0x481a6000, ap 40 16.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart4";
 			reg = <0xa6050 0x4>,
 			      <0xa6054 0x4>,
 			      <0xa6058 0x4>;
@@ -1414,7 +1410,6 @@ uart3: serial@0 {
 
 		target-module@a8000 {			/* 0x481a8000, ap 42 20.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart5";
 			reg = <0xa8050 0x4>,
 			      <0xa8054 0x4>,
 			      <0xa8058 0x4>;
@@ -1443,7 +1438,6 @@ uart4: serial@0 {
 
 		target-module@aa000 {			/* 0x481aa000, ap 44 12.0 */
 			compatible = "ti,sysc-omap2", "ti,sysc";
-			ti,hwmods = "uart6";
 			reg = <0xaa050 0x4>,
 			      <0xaa054 0x4>,
 			      <0xaa058 0x4>;