WifiNative.cpp: reduce logspam

We sometimes fetch the channel list often (every 20 seconds),
so logging the message on every attempt to fetch the list is
spammy.

Demote the message to verbose level, to reduce spam.

BUG=28425940
TEST=manual

Manual test:
- install new code
- reboot device
- after reboot, sleep 60
$ adb logcat -d \
  | egrep 'getting valid|ScannerImpl: Starting wifi scan for freqs'
  -> match for "ScannerImpl...", but not "getting valid"

Change-Id: I56a8f941ced0f291f0c37e9279e5dda635351cb2
1 file changed
tree: 0e3b2dcea1a7757028fe6b8915a2cbd3120d7c4f
  1. service/
  2. tests/