parisc: Add alternative patching to synchronize_caches define

#ifndef __ASM_BARRIER_H

#define __ASM_BARRIER_H

#include <asm/alternative.h>

#ifndef __ASSEMBLY__

/* The synchronize caches instruction executes as a nop on systems in

   which all memory references are performed in order. */

#define synchronize_caches() __asm__ __volatile__ ("sync" : : : "memory")

#define synchronize_caches() asm volatile("sync" \

	ALTERNATIVE(ALT_COND_NO_SMP, INSN_NOP) \

	: : : "memory")

#if defined(CONFIG_SMP)

#define mb()		do { synchronize_caches(); } while (0)