ARM: dts: msm: Add regulator entries for UFS device on 8084

UFS device attached to UFS host on APQ8084 is powered by at most
three PMIC regulators - LDO_19(VCC), LDO_3(VCCQ), SMPS_4(VCCQ2).
Add entries for these in UFS host controller device node.

Change-Id: I2152391490859ec68046ef24a9bd5fd540c14f1a
Signed-off-by: Sujit Reddy Thumma <sthumma@codeaurora.org>