phy: qcom-ufs: add MODULE_LICENSE tag

While the specific UFS PHY drivers (14nm and 20nm) have a module
license, the common base module does not, leading to a Kbuild
failure:

WARNING: modpost: missing MODULE_LICENSE() in drivers/phy/qualcomm/phy-qcom-ufs.o
FATAL: modpost: GPL-incompatible module phy-qcom-ufs.ko uses GPL-only symbol 'clk_enable'

This adds a module description and license tag to fix the build.
I added both Yaniv and Vivek as authors here, as Yaniv sent the initial
submission, while Vivek did most of the work since.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>