MAINTAINERS: Add maintainer for Qualcomm crypto drivers

There is no maintainer for Qualcomm crypto drivers and we are seeing more
development in this area. Add myself as the maintainer so that I can help
in reviewing the changes submitted to these drivers.

Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>