drm/msm/dsi-staging: use display panel's force_clk_lane_hs instead of phy's

in order to dsi panel and dsi2hdmi panel compatible,
but dsi panel don't need force_clk_lane_hs property,
so delete phy's "qcom,panel-force-clock-lane-hs" property read,
and change phy->cfg.force_clk_lane_hs to use display panel's
force_clk_lane_hs.

Signed-off-by: Chong Gu <chongu@codeaurora.org>
Change-Id: I490e08b2ee859797c2b3aeddf109a3a4286fb922