arm: fix implicit memset/string.h usage in various arch/arm files

To fix things like this:

arch/arm/mach-omap2/usb-tusb6010.c:58: error: implicit declaration of function 'memset'
arch/arm/kernel/leds.c:40: error: implicit declaration of function 'strcspn'
arch/arm/kernel/leds.c:40: warning: incompatible implicit declaration of built-in function 'strcspn'
arch/arm/kernel/leds.c:45: error: implicit declaration of function 'strncmp'
arch/arm/kernel/leds.c:55: error: implicit declaration of function 'strlen'
arch/arm/kernel/leds.c:55: warning: incompatible implicit declaration of built-in function 'strlen'
arch/arm/mach-omap2/clockdomain.c:52: error: implicit declaration of function 'strcmp'
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

arch/arm/kernel/leds.c

@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/sysdev.h>
 #include <linux/syscore_ops.h>
+#include <linux/string.h>
 
 #include <asm/leds.h>
 

arch/arm/mach-omap2/clockdomain.c

@@ -17,6 +17,7 @@
 #include <linux/device.h>
 #include <linux/list.h>
 #include <linux/errno.h>
+#include <linux/string.h>
 #include <linux/delay.h>
 #include <linux/clk.h>
 #include <linux/limits.h>

arch/arm/mach-omap2/display.c

@@ -15,6 +15,7 @@
  * GNU General Public License for more details.
  */
 
+#include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/platform_device.h>

arch/arm/mach-omap2/gpmc-onenand.c

@@ -10,6 +10,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/string.h>
 #include <linux/kernel.h>
 #include <linux/platform_device.h>
 #include <linux/mtd/onenand_regs.h>

arch/arm/mach-omap2/usb-tusb6010.c

@@ -8,6 +8,7 @@
  * published by the Free Software Foundation.
  */
 
+#include <linux/string.h>
 #include <linux/types.h>
 #include <linux/errno.h>
 #include <linux/delay.h>