nds32: 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>
Reviewed-by: Jagan Teki <jteki@openedev.com>

arch/nds32/include/asm/bitops.h

@@ -21,6 +21,10 @@
 #ifdef __KERNEL__
 
 #include <asm/system.h>
+#include <asm-generic/bitops/fls.h>
+#include <asm-generic/bitops/__fls.h>
+#include <asm-generic/bitops/fls64.h>
+#include <asm-generic/bitops/__ffs.h>
 
 #define smp_mb__before_clear_bit()	do { } while (0)
 #define smp_mb__after_clear_bit()	do { } while (0)