linux-imx

fscrypt: introduce helper function for filename matching

Introduce a helper function fscrypt_match_name() which tests whether a
fscrypt_name matches a directory entry.  Also clean up the magic numbers
and document things properly.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>