MAINTAINERS: Add Delta Networks TN48M CPLD drivers

Add maintainers entry for the Delta Networks TN48M
CPLD MFD drivers.

Signed-off-by: Robert Marko <robert.marko@sartura.hr>
Link: https://lore.kernel.org/r/20220131133049.77780-7-robert.marko@sartura.hr


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>