MAINTAINERS: drop myself from PM AVS drivers

I haven't had the time or the expertise to adequately review and
maintain these drivers for awhile, so make it official.

Signed-off-by: Kevin Hilman <khilman@baylibre.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: khilman

MAINTAINERS

@@ -5380,7 +5380,6 @@ F:	include/linux/kobj*
 F:	lib/kobj*
 
 DRIVERS FOR ADAPTIVE VOLTAGE SCALING (AVS)
-M:	Kevin Hilman <khilman@kernel.org>
 M:	Nishanth Menon <nm@ti.com>
 L:	linux-pm@vger.kernel.org
 S:	Maintained