clk: qcom: update the clock structures for DP clocks for SDM660

clk: qcom: update the clock structures for DP clocks for SDM660

Update the clock names for parents of MDSS display port source
clocks for SDM660. The clock frequencies of DP clocks are
requested by the MDSS display port driver in order of KHz to
avoid integer overflow issues on 32-bit builds. Update the same
for DP clock structures in clock driver.

Change-Id: Ibfdade6f2db5c9ec7a7ff53ba76e6db53e4e605e
Signed-off-by: Padmanabhan Komanduru <pkomandu@codeaurora.org>