ARM: dts: msm: Change the resource name for LPI CX/MX regulators

SDM660 has LPI (and not SSC) which uses "rwlc" and "rwlm"
as the regulator resource names. Use the same.

Change-Id: I88038d0b7ae5b73e03154cf0d03c16a2fd69fc5e
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>