Move __set/clear_bit from ubifs.h to bitops.h

__set_bit and __clear_bit are defined in ubifs.h as well as in
asm/include/bitops.h for some architectures. This patch moves
the generic implementation to include/linux/bitops.h and uses
that unless it's defined by the architecture.

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>

include/asm-microblaze/bitops.h

@@ -75,6 +75,7 @@ extern __inline__ void __set_bit(int nr, volatile void * addr)
 	mask = 1 << (nr & 0x1f);
 	*a |= mask;
 }
+#define __set_bit
 
 /*
  * clear_bit() doesn't provide any barrier for the compiler.