ext4: print file system UUID on mount, remount and unmount

ext4: print file system UUID on mount, remount and unmount

The device names are not necessarily consistent across reboots which can
make it more difficult to identify the right file system when tracking
down issues using system logs.

Print file system UUID string on every mount, remount and unmount to
make this task easier.

This is similar to the functionality recently propsed for XFS.

Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Cc: Lukas Herbolt <lukas@herbolt.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/20221108145042.85770-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>