drm/i915: Don't spew errors when resetting HDMI scrambling/bit clock ratio fails

drm/i915: Don't spew errors when resetting HDMI scrambling/bit clock ratio fails

When we're disabling the HDMI link we try to reset the scrambling and
TMDS bit clock ratio back to the default values. This will fail if the
sink has already been disconnected. Thus we should not print an error
message when resetting the scrambling/TMDS bit clock ratio fail during
disable. During enable we do want the error, and during disable we may
still want to know what happended for debug purposes so let's use
DRM_DEBUG_KMS() there.

v2: Remember them consts
v3: Go back to just one function and print the errors/debugs
    from callers (Shashank)

Cc: Shashank Sharma <shashank.sharma@intel.com>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105644
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105655
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180322154707.22103-1-ville.syrjala@linux.intel.com
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>