include/bitmap.h: add new functions to documentation

I found these functions only by chance although I was looking exactly
for something like them. So, add them to the list of functions to make
them more visible.

Fixes: e837dfde15 ("bitmap: genericize percpu bitmap region iterators")
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>

include/linux/bitmap.h

@@ -51,6 +51,12 @@
  *  bitmap_clear(dst, pos, nbits)               Clear specified bit area
  *  bitmap_find_next_zero_area(buf, len, pos, n, mask)  Find bit free area
  *  bitmap_find_next_zero_area_off(buf, len, pos, n, mask, mask_off)  as above
+ *  bitmap_next_clear_region(map, &start, &end, nbits)  Find next clear region
+ *  bitmap_next_set_region(map, &start, &end, nbits)  Find next set region
+ *  bitmap_for_each_clear_region(map, rs, re, start, end)
+ *  						Iterate over all clear regions
+ *  bitmap_for_each_set_region(map, rs, re, start, end)
+ *  						Iterate over all set regions
  *  bitmap_shift_right(dst, src, n, nbits)      *dst = *src >> n
  *  bitmap_shift_left(dst, src, n, nbits)       *dst = *src << n
  *  bitmap_cut(dst, src, first, n, nbits)       Cut n bits from first, copy rest