mkfs-util: turn quiet/discard to a flags field

Add a new `MakeFilesystemFlags` enum and use it to replace the existing
`quiet` and `discard` booleans on `make_filesystem()`.

Update the callers.  While we're doing that, consolidate some duplicated
logic in systemd-repart.

Signed-off-by: Allison Karlitskaya <allison.karlitskaya@redhat.com>

src/home/homework-luks.c

@@ -2382,8 +2382,7 @@ int home_create_luks(
                             user_record_user_name_and_realm(h),
                             /* root = */ NULL,
                             fs_uuid,
-                            user_record_luks_discard(h),
-                            /* quiet = */ true,
+                            (user_record_luks_discard(h) ? MKFS_DISCARD : 0) | MKFS_QUIET,
                             /* sector_size = */ 0,
                             /* compression = */ NULL,
                             /* compression_level= */ NULL,