Now that RPMh supports the higher voltages needed from PM8350
LDO 7, replace the stub-regulator device for PM8350 LDO 7 with an
rpmh-regulator device. This ensures that consumers are able to
modify the physical state of this PMIC regulator.
Change-Id: I370622f9cb309f50b4ed7cff57807436ae3cd31f