devpts: Fix type for uid and gid params

Fix devpts to parse uid and gid params using the correct type so that they
get interpreted in the context of the user namespace.

Fixes: cc0876f8 ("vfs: Convert devpts to use the new mount API")
Reported-by: Debarshi Ray <dray@redhat.com>
Closes: https://github.com/containers/podman/issues/25751


Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Link: https://lore.kernel.org/r/759134.1743596274@warthog.procyon.org.uk


cc: Eric Sandeen <sandeen@redhat.com>
cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>