bitmap: add bitmap_copy_le()

bitmap_copy_le() copies a bitmap, putting the bits into little-endian
order (i.e., each unsigned long word in the bitmap is put into
little-endian order).

The UWB stack used bitmaps to manage Medium Access Slot availability,
and these bitmaps need to be written to the hardware in LE order.

Signed-off-by: David Vrabel <david.vrabel@csr.com>
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
index 89781fd..5379913 100644
--- a/include/linux/bitmap.h
+++ b/include/linux/bitmap.h
@@ -130,6 +130,7 @@
 extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order);
 extern void bitmap_release_region(unsigned long *bitmap, int pos, int order);
 extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order);
+extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits);
 
 #define BITMAP_LAST_WORD_MASK(nbits)					\
 (									\