ARM: dts: msm: Update LDO for PCIe EP on SDX20

PCIe uses L1 LDO for SDX20. Update LDO number and voltage levels
that are needed for LDO accordingly for PCIe EP mode.

Change-Id: I5514747d1a42ea370e1779db9702959818cc6e83
Signed-off-by: Rama Krishna Phani A <rphani@codeaurora.org>