[ports-gcc] Unbreak audio/mumble

> http://build-failures.rhaalovely.net/sparc64/2020-03-01/audio/mumble.log

I've just disabled pre compilated headers for base-gcc archs, then it
builds without issues on powerpc [0], with Qt 5.13.2. No revision bump
needed, this version never built on sparc64 and powerpc.

Comments/feedback are welcome,

Charlène.


[0] https://bin.charlenew.xyz/mumble-1.3.0.log


Index: Makefile
===================================================================
RCS file: /cvs/ports/audio/mumble/Makefile,v
retrieving revision 1.36
diff -u -p -u -p -r1.36 Makefile
--- Makefile 25 Feb 2020 05:14:52 -0000 1.36
+++ Makefile 5 Mar 2020 18:20:29 -0000
@@ -64,6 +64,12 @@ ALL_TARGET = release

NO_TEST = Yes

+.include <bsd.port.arch.mk>
+# pre compilated headers are invalid on gcc archs
+.if ${PROPERTIES:Mgcc4}
+MODQMAKE_ARGS += CONFIG+=no-pch
+.endif
+
pre-configure:
cd ${WRKSRC}/src/mumble/ && QTDIR=${WRKDIR}/bin \
${MODQT_LRELEASE} *.ts