MAINTAINERS: Update brcmstb entry
MAINTAINERS: Update brcmstb entry

We have not heard back from Marc in a while, since we last asked him to
ack/nack this change here: https://lkml.org/lkml/2015/1/14/1004

This was back in January, we are in the 3.21^W4.1 merge window now, so,
as outlined in this email thread, remove him from the MAINTAINERS list
now.

Signed-off-by: Florian Fainelli <59190c1867e3222b932a0de3c668eb2d980d69a2@gmail.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs