microblaze: Use the generic bitops headers

The generic bitops headers are required when calling logarithmic
functions, such as ilog2().

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
diff --git a/arch/microblaze/include/asm/bitops.h b/arch/microblaze/include/asm/bitops.h
index 0ac78d7..d24f2cf 100644
--- a/arch/microblaze/include/asm/bitops.h
+++ b/arch/microblaze/include/asm/bitops.h
@@ -7,6 +7,10 @@
 
 #include <asm/byteorder.h>	/* swab32 */
 #include <asm/system.h>		/* save_flags */
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/__ffs.h>
 
 #ifdef __KERNEL__
 /*