[PATCH] PPC64 had _raw_read_trylock already

Ingo presumably didn't notice that ppc64 already had a functional
_raw_read_trylock when he added the #define to use the generic
version.  This just removes the #define so we use the ppc64-specific
version again.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/asm-ppc64/spinlock.h

@@ -222,8 +222,6 @@ static void __inline__ _raw_read_unlock(rwlock_t *rw)
 	: "cr0", "memory");
 }
 
-#define _raw_read_trylock(lock) generic_raw_read_trylock(lock)
-
 /*
  * This returns the old value in the lock,
  * so we got the write lock if the return value is 0.