netfs: add Paulo as maintainer and remove myself as Reviewer

My role has changed since I originally agreed to help with netfs, and
I'm no longer providing a lot of value here. Luckily, Paulo has agreed
to step in as co-maintainer.

Acked-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Link: https://lore.kernel.org/r/20250324-master-v1-1-e2dd2fdb15b4@kernel.org
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: jtlayton

MAINTAINERS

@@ -8949,7 +8949,7 @@ F:	include/linux/iomap.h
 
 FILESYSTEMS [NETFS LIBRARY]
 M:	David Howells <dhowells@redhat.com>
-R:	Jeff Layton <jlayton@kernel.org>
+M:	Paulo Alcantara <pc@manguebit.com>
 L:	netfs@lists.linux.dev
 L:	linux-fsdevel@vger.kernel.org
 S:	Supported