MAINTAINERS: Fold "Block QAPI, monitor, ..." into "Block layer core"

MAINTAINERS: Fold "Block QAPI, monitor, ..." into "Block layer core"

Section "Block QAPI, monitor, command line" is about the external
interfaces we provide for block devices.  It covers the relevant QAPI
schema parts, monitor and command line code, more or less.

The section's files are also covered by section "Block layer core",
except for the QAPI schema files.

I haven't acted as maintainer in this area for a long time.  Make it
official: add the QAPI schema files to section "Block layer core", and
delete section "Block QAPI, monitor, command line".

Cc: Kevin Wolf <kwolf@redhat.com>
Cc: Hanna Reitz <hreitz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20221020120541.80757-1-armbru@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>