drm/msm/dp: abort connect processing if cable is disconnected

In case DP cable is disconnected immediately after connect, abort
any processing DP driver is doing like reading EDID or DPCD or
link maintenance etc which requires AUX communication.
The AUX communication needs a physical connection with sink. If
it has already been broken, AUX communication will continue to
fail. Abort such transactions on disconnect to avoid unnecessary
delays in disconnect or next connect processing.

CRs-Fixed: 2184573
Change-Id: Id9e61169363ab94f7eb3d069aefb3b19f2d46b75
Signed-off-by: Ajay Singh Parmar <aparmar@codeaurora.org>