staging: r8188eu: remove unused bitshift function

The bitshift function from osdep_service.h is not used.
Remove it.
Signed-off-by: Martin Kaiser <martin@kaiser.cx>
Link: https://lore.kernel.org/r/20220115165536.231210-4-martin@kaiser.cxSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/r8188eu/include/osdep_service.h

@@ -163,15 +163,6 @@ static inline u32 _RND512(u32 sz)
 	return val;
 }
 
-static inline u32 bitshift(u32 bitmask)
-{
-	u32 i;
-
-	for (i = 0; i <= 31; i++)
-		if (((bitmask>>i) &  0x1) == 1) break;
-	return i;
-}
-
 /*  limitation of path length */
 #define PATH_LENGTH_MAX PATH_MAX