MAINTAINERS: Replace IRC with DISCORD
MAINTAINERS: Replace IRC with DISCORD

Discord is becoming the chat server of choice.

Signed-off-by: Deepak Kodihalli <c977ddd415963f49ebc01f65d1c96b215095fa0d@gmail.com>
Change-Id: I7cd09e4fb8cc6d0896ae8854f43f361ab8c9b389

openbmc/pldm,openbmc/pldm,openbmc/pldm