[ARM] Fix warning in arch/arm/kernel/semaphore.c

Newer binutils complains:
/tmp/cc07pbI9.s:146: Warning: ignoring changed section type for .sched.text

Fix this warning by adding %progbits to the .section.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/kernel/semaphore.c

@@ -178,7 +178,7 @@ int __down_trylock(struct semaphore * sem)
  * registers (r0 to r3 and lr), but not ip, as we use it as a return
  * value in some cases..
  */
-asm("	.section .sched.text,\"ax\"		\n\
+asm("	.section .sched.text,\"ax\",%progbits	\n\
 	.align	5				\n\
 	.globl	__down_failed			\n\
 __down_failed:					\n\