bcm968380gerg: Add MAINTAINERS file

Add an initial MAINTAINERS file based on author of the code.

Cc: Philippe Reynes <philippe.reynes@softathome.com>
Signed-off-by: NTom Rini <trini@konsulko.com>

board/broadcom/bcm968380gerg/MAINTAINERS

+BCM968380GERG BOARD
+M:	Philippe Reynes <philippe.reynes@softathome.com>
+S:	Maintained
+F:	board/broadcom/bcm968380gerg/
+F:	include/configs/broadcom_bcm968380gerg.h
+F:	configs/bcm968380gerg_ram_defconfig