MAINTAINERS: add entry for AMD energy driver

The kernel driver is part of HWMON subsystem.

Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Naveen Krishna Chatradhi <nchatrad@amd.com>
Link: https://lore.kernel.org/r/20200519155011.56184-3-nchatrad@amd.com


Signed-off-by: Guenter Roeck <linux@roeck-us.net>