[PATCH] M68k {,smp_}read_barrier_depends()

Add definitions for {,smp_}read_barrier_depends()

include/asm-m68k/system.h

@@ -74,12 +74,14 @@ static inline int irqs_disabled(void)
 #define mb()		barrier()
 #define rmb()		barrier()
 #define wmb()		barrier()
+#define read_barrier_depends()	do { } while(0)
 #define set_mb(var, value)    do { xchg(&var, value); } while (0)
 #define set_wmb(var, value)    do { var = value; wmb(); } while (0)
 
 #define smp_mb()	barrier()
 #define smp_rmb()	barrier()
 #define smp_wmb()	barrier()
+#define smp_read_barrier_depends()	do { } while(0)
 
 
 #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))