MAINTAINERS: cpufreq: amd-pstate: Add co-maintainers and reviewer

I'm happy to add Gautham and Mario as the co-maintainers, Perry as the
reviewer for amd-pstate driver.

Signed-off-by: Huang Rui <ray.huang@amd.com>
Acked-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

Author: huangrui

MAINTAINERS

@@ -1062,6 +1062,9 @@ F:	drivers/gpu/drm/amd/pm/
 
 AMD PSTATE DRIVER
 M:	Huang Rui <ray.huang@amd.com>
+M:	Gautham R. Shenoy <gautham.shenoy@amd.com>
+M:	Mario Limonciello <mario.limonciello@amd.com>
+R:	Perry Yuan <perry.yuan@amd.com>
 L:	linux-pm@vger.kernel.org
 S:	Supported
 F:	Documentation/admin-guide/pm/amd-pstate.rst