%{threadid} should have been %{qthreadptr} but we forgot to make the
change for Qt 5.4. So do it now.
[ChangeLog][QtCore][Logging framework] %{threadid} now prints the real
thread ID. On Linux, OS X, iOS, FreeBSD and Windows, the value is unique
system-wide. On other systems, it will print something that may be
process-specific (the value of pthread_self(3)). To print the pointer
to QThread::current(), use %{qthreadptr}.
Change-Id: Ie383ff864a11966cf5d095b966a30ace65d34ee6
Reviewed-by: Olivier Goffart <ogoffart@woboq.com>