clk: qcom: mdss: improve DSI PLL's performance

To improve performance margin for DSI's PLL at cold temperature case,
the value of DSIPHY_PLL_PLL_ICPMSET should be changed from 0x24 to 0x3f.

Change-Id: I139e37e137355c5e8f0b3bebd28b23a09593dd13
Signed-off-by: Guchun Chen <guchunc@codeaurora.org>