f2fs: rename f2fs_set/clear_bit to f2fs_test_and_set/clear_bit

Rename f2fs_set/clear_bit to f2fs_test_and_set/clear_bit, which mean
set/clear bit and return the old value, for better readability.

Signed-off-by: Gu Zheng <guz.fnst@cn.fujitsu.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2 files changed