drm: keep connector status change logging human readable

We've had human readable connector status change debug logging since

commit ed7951dc
Author: Lespiau, Damien <damien.lespiau@intel.com>
Date:   Fri May 10 12:36:42 2013 +0000

    drm: Make the HPD status updates debug logs more readable

but

commit 162b6a57
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Wed Jan 21 08:45:21 2015 +0100

    drm/probe-helper: don't lose hotplug event

added a new one with just the numbers. Fix it.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/1449144003-2877-1-git-send-email-jani.nikula@intel.com