clk: qcom: mdss: add DSI PLL clock driver support for 8916

This change adds the DSI PLL clock driver support for
8916. In addition, it adds support of DSI PLL programming
of different MDSS revisions using the same DSI PLL driver.
Also rename the compatibility string of the DSI
PLL handle so that the detection and support of DSI
PLL driver for 8974 and 8916 happens dynamically.

Change-Id: I169ebeaf23e4be8ff4b533fce1057144edd8b692
Signed-off-by: Jeevan Shriram <jshriram@codeaurora.org>
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>