ARM: 8438/1: Add unwinding to __clear_user_std()

Add unwinding annotations so that unwinding from this function
works properly.

Signed-off-by: Stephen Boyd <[e-mail]>
Signed-off-by: Russell King <[e-mail]>

arch/arm/lib/clear_user.S

···
  */
 #include <linux/linkage.h>
 #include <asm/assembler.h>
+#include <asm/unwind.h>
 
 		.text
 
···
  */
 ENTRY(__clear_user_std)
 WEAK(arm_clear_user)
+UNWIND(.fnstart)
+UNWIND(.save {r1, lr})
 		stmfd	sp!, {r1, lr}
 		mov	r2, #0
 		cmp	r1, #4
···
 USER(		strnebt	r2, [r0])
 		mov	r0, #0
 		ldmfd	sp!, {r1, pc}
+UNWIND(.fnend)
 ENDPROC(arm_clear_user)
 ENDPROC(__clear_user_std)