drm/msm/dp: initialize host on configure call

Some sinks set HPD high only after the source host
is initialized. Once the PD communication is completed,
initialize the host on configure call so that such sinks
can set HPD high on cable connection.

Change-Id: Ic1ba6be09e71abf286021533fdb6f4dc68531d35
CRs-Fixed: 2326085
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>
Signed-off-by: Abhijith Desai <desaia@codeaurora.org>