MAINTAINERS: Update module subsystem maintainers and repository

MAINTAINERS: Update module subsystem maintainers and repository

Add myself as a maintainer for module support as I'll be handling pull
requests for the next six months according to the previously announced
rotation [1][2].  Also, update the git repository link to point to the
modules tree, which is already used by linux-next.

Link: https://lore.kernel.org/linux-modules/Z3gDAnPlA3SZEbgl@bombadil.infradead.org
Link: https://lore.kernel.org/linux-modules/20251203234840.3720-1-da.gomez@kernel.org/
Acked-by: Daniel Gomez <da.gomez@samsung.com>
Acked-by: Petr Pavlu <petr.pavlu@suse.com>
Reviewed-by: Aaron Tomlin <atomlin@atomlin.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>