ASoC: Add Jassi Brar as Samsung maintainer

Since Jassi is doing so much good work and can offer such good review
for the Samsung CPU support add an entry for the Samsung ASoC drivers
to MAINTAINERS listing him.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>