disp: msm: dsi: move dsi pll as subnode to dsi PHY

DSI PLL is tightly coupled with DSI PHY. This change removes
separate DSI pll driver and makes DSI pll as a subnode to DSI
PHY which is an accurate way of representation. In addition, this
change adds support for 5nm DSI ctrl and PHY revisions and adds
DSI pll support for 5nm. Remove support for older DSI pll revisions
such as 7nm, 10nm, 14nm, 20nm, 28nm.

Change-Id: Ic8b886a9fe24b906e4ec5130720600efa1e59b68
Signed-off-by: Satya Rama Aditya Pinapala <psraditya30@codeaurora.org>