[ARM] remove memzero()

As suggested by Andrew Morton, remove memzero() - it's not supported
on other architectures so use of it is a potential build breaking bug.
Since the compiler optimizes memset(x,0,n) to __memzero() perfectly
well, we don't miss out on the underlying benefits of memzero().

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/include/asm/processor.h

@@ -64,7 +64,7 @@ struct thread_struct {
 ({									\
 	unsigned long *stack = (unsigned long *)sp;			\
 	set_fs(USER_DS);						\
-	memzero(regs->uregs, sizeof(regs->uregs));			\
+	memset(regs->uregs, 0, sizeof(regs->uregs));			\
 	if (current->personality & ADDR_LIMIT_32BIT)			\
 		regs->ARM_cpsr = USR_MODE;				\
 	else								\