f2fs: check cap_resource only for data blocks

Cherry-pick from origin/upstream-f2fs-stable-linux-4.14.y:
commit ca17de43 ("f2fs: check cap_resource only for data blocks")

This patch changes the rule to check cap_resource for data blocks, not inode
or node blocks in order to avoid selinux denial.

Change-Id: Icf0ce297701d20d288f3f08cd94f3b7c9348f79c
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>