Add support for using qCDebug and friends in the 'printf style' way.
This allows an almost mechanical conversion of existing qDebug, qWarning,
qCritical macros, and allows avoiding the size overhead the streaming
style incurs (mostly due to inlined QDebug code).
To handle this gracefully we require variadic macros (part of
C++11/C99). For compilers not supporting variadic macros we fall back
to checking the category in QMessageLogger.
[ChangeLog][QtCore][Logging] Allow qCDebug macros to be used in a printf
style.
Change-Id: I5a8fb135dca504e1d621bb67bf4b2a50c73d41b9
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
b8a38a6737