mx6sabresd: Add mx6sabresd_spl_defconfig to MAINTAINERS entry

Let's add mx6sabresd_spl_defconfig entry into MAINTAINERS, so that we avoid
getting a warning that the mx6sabresd_spl is not maintained.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
1 file changed