Remove incorrect error-level logging

TimeZoneFinder logs when it can't find a file in the
createInstanceWithFallback(). The lack of a file is expected
(hence "fallback") so logging at error is unnecessarily
alarmist. The logging has been removed unless no files
can be found.

Bug: 63208076
Test: make
Change-Id: I49671247cb670ad814870f1ef89014975ba7d777
1 file changed