ext4: Always journal quota file modifications

When journaled quota options are not specified, we do writes
to quota files just in data=ordered mode. This actually causes
warnings from JBD2 about dirty journaled buffer because ext4_getblk
unconditionally treats a block allocated by it as metadata. Since
quota actually is filesystem metadata, the easiest way to get rid
of the warning is to always treat quota writes as metadata...

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>