adb: call android::base::InitLogging even when adb tracing is disabled

This is a follow-up to https://android-review.googlesource.com/153623


which prevented android::base::InitLogging() from being called when
tracing was disabled.

It is ok to call InitLogging() on a device or host because calling it
does not imply that a logging file is used, which was the reason for
not calling it on a device.

So this change should preserve the device behavior of not using a
logging file when tracing is disabled, plus it will call InitLogging()
all the time in case logging APIs are called.

Change-Id: I3fd6ba2c567f67a2f111a85f174893fbf866ec57
Signed-off-by: Spencer Low <CompareAndSwap@gmail.com>