clk: qcom: mdss: Add check to read the gdsc status

Add check for 28NM pll interface to read the
gdsc status bit for QM215 target.

Change-Id: I3167950ce4ec16e553e15330f5deb6de4a3619c4
Signed-off-by: Raghavendra Ambadas <rambad@codeaurora.org>
Signed-off-by: Nirmal Abraham <nabrah@codeaurora.org>