v3/ec: change log level to INF

Make the logging a little more verbose, particularly for the IT68051
code which uses LOG_INF in several places.

BUG=None
TEST=Connect a DisplayPort source (such as a Chromebook with a USB-C
to DisplayPort adapter) and observe output on the Chameleon serial
console showing the detection of the video signal, e.g.
`[00:02:05.838,000] <inf> it68051: # SCDT ON #`

Change-Id: If4e4bb9826c0bb4e10caca3d751a2b6191d73cf4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/chameleon/+/2847582
Tested-by: Paul Fagerburg <pfagerburg@chromium.org>
Auto-Submit: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Alexandru M Stan <amstan@chromium.org>
Commit-Queue: Alexandru M Stan <amstan@chromium.org>
1 file changed