MAINTAINERS: Add keyword pattern for hwmon registration functions

A pattern match for hardware monitoring registration functions ensures
that hardware monitoring maintainers are copied whenever hardware
monitoring drivers are added to the tree.

Reviewed-by: Jean Delvare <[e-mail]>
Signed-off-by: Guenter Roeck <[e-mail]>

MAINTAINERS

···
 F:	drivers/hwmon/
 F:	include/linux/hwmon*.h
 F:	include/trace/events/hwmon*.h
+K:	(devm_)?hwmon_device_(un)?register(|_with_groups|_with_info)
 
 HARDWARE RANDOM NUMBER GENERATOR CORE
 M:	Matt Mackall <[e-mail]>