ARM: dts: msm: add PMIC GPIO devices for SDM855

Add GPIO peripheral devices for PM855, PM855B, and PM855L.
These devices allow consumers to manage individual GPIO pins.

Change-Id: I16d931a02f8165c016f6c8cbfc08e3d0f4dac5f1
Signed-off-by: David Collins <collinsd@codeaurora.org>