mdss: display: replace byte string with struct dsi_panel_cmd

Convert dcs byte string from dtsi file to dcs command list.
Also group dcs command list and link state into dsi_panel_cmd
struct to keep backward compartibllity.

Change-Id: Iff35bd7b0c0e03c2b341e501290b15e1621501d1
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>