msm: mdss: hdmi: enable ddc gpios before any ddc transaction

Enable DDC power module and corresponding GPIOs before EDID read,
write, HDCP authentication and SCDC communication with sink to
avoid any DDC read or write failures.

Change-Id: Ia88c616d7a6149c3be190b5fbab22444448aea5d
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>