Add kernel log for HDMI hotplug event

The test will try to capture the dmesg update for the HDMI plug/unplug

Example output:
[  160.307914] mediatek-cec 1001a000.cec: hotplug event! cur hpd = 1, hpd = 0
[  160.337206] mediatek-cec 1001a000.cec: hotplug event! cur hpd = 0, hpd = 1

Change-Id: Iae611482707214a7d735bdd46ec6ad18e7ca1dd5
1 file changed