phy: qcom-qmp: Add SW reset register

For V4 QMP UFS Phy, we need to assert reset bits, configure the phy and
then deassert it, so add the QPHY_SW_RESET register which does this.

Signed-off-by: Vinod Koul <vkoul@kernel.org>
Reviewed-by: Manu Gautam <mgautam@codeaurora.org>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>