f2fs: convert to use bitmap API

[ Upstream commit 447286eb ]

Let's use BIT() and GENMASK() instead of open it.

Signed-off-by: Yangtao Li <frank.li@vivo.com>
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Stable-dep-of: f5f3bd90 ("f2fs: set the default compress_level on ioctl")
Signed-off-by: Sasha Levin <sashal@kernel.org>