MAINTAINERS: Add entry for Compute Express Link Emulation

The CXL emulation will be jointly maintained by Ben Widawsky
and Jonathan Cameron.  Broken out as a separate patch
to improve visibility.

Signed-off-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220429144110.25167-4-Jonathan.Cameron@huawei.com>

MAINTAINERS

@@ -2545,6 +2545,13 @@ F: qapi/block*.json
 F: qapi/transaction.json
 T: git https://repo.or.cz/qemu/armbru.git block-next
 
+Compute Express Link
+M: Ben Widawsky <ben.widawsky@intel.com>
+M: Jonathan Cameron <jonathan.cameron@huawei.com>
+S: Supported
+F: hw/cxl/
+F: include/hw/cxl/
+
 Dirty Bitmaps
 M: Eric Blake <eblake@redhat.com>
 M: Vladimir Sementsov-Ogievskiy <v.sementsov-og@mail.ru>