bitmap: Make bitmap_remap() and bitmap_bitremap() available to users

Currently the bitmap_remap() and bitmap_bitremap() are available
only for CONFIG_NUMA=y case, while some users may benefit out of it
and being independent to NUMA code. Make them available to users
by moving out of ifdeffery and exporting for modules.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Neeli Srinivas <sneeli@xilinx.com>
Acked-by: Yury Norov <yury.norov@gmail.com>
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>