Replace for_each_*_bit_from() with for_each_*_bit() where appropriate

A couple of kernel functions call for_each_*_bit_from() with start
bit equal to 0. Replace them with for_each_*_bit().

No functional changes, but might improve on readability.

Signed-off-by: Yury Norov <yury.norov@gmail.com>
Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com>