[ARM] 5152/1: Add myself to tosa maintainers list

Since the beginning of this year I'm providing fixes and updates
for the Sharp SL-6000 (tosa). Add myself as one of the maintainers
of the machine.

Cc: Dirk Opfer <dirk@opfer-online.de>
Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Acked-by: Eric Miao <eric.miao@marvell.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>