Restore __ALIGN_MASK()

Fix lib/bitmap.c compile failure due to __ALIGN_KERNEL changes.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>

include/linux/kernel.h

@@ -40,6 +40,7 @@ extern const char linux_proc_banner[];
 #define STACK_MAGIC	0xdeadbeef
 
 #define ALIGN(x, a)		__ALIGN_KERNEL((x), (a))
+#define __ALIGN_MASK(x, mask)	__ALIGN_KERNEL_MASK((x), (mask))
 #define PTR_ALIGN(p, a)		((typeof(p))ALIGN((unsigned long)(p), (a)))
 #define IS_ALIGNED(x, a)		(((x) & ((typeof(x))(a) - 1)) == 0)