clk: qcom: add MDSS PLL support for sdm630

Add the sdm630 compatible string to MDSS PLL driver
of_device_id table list, so that initialization of
MDSS PLL driver takes place for sdm630 platform.

Change-Id: I284ff9c07a4a971260ade399a2f7a605003ccf1d
Signed-off-by: Sandeep Panda <spanda@codeaurora.org>