dev: gcdb: add support to specify the DSI PLL from fastboot oem

For single/split DSI cases, depending on the DSI PHY version, there
is support to select DSI PLL0/PLL1 to drive the DSI controller/PHY.
Add support to specify this using fastboot oem command.

Example:
fastboot oem select-display-panel jdi_1080p_video:pll0
fastboot oem select-display-panel jdi_1080p_video:pll0:disable
fastboot oem select-display-panel jdi_1080p_video:pll1#sim-swte:disable
fastboot oem select-display-panel jdi_1080p_video:skip:pll1

Change-Id: Ie74710c3047ccca4addd9c00611682b726befb76
4 files changed