gst-plugins-bad: pass -fext-numeric-literals to make gcc happy

mingw-w64-gst-plugins-bad/PKGBUILD

@@ -106,6 +106,10 @@ prepare() {
 build() {
   mkdir -p "${srcdir}/build-${MSYSTEM}" && cd "${srcdir}/build-${MSYSTEM}"
 
+  if [[ ${CC} == gcc ]]; then
+    CXXFLAGS+=" -fext-numeric-literals"
+  fi
+
   MSYS2_ARG_CONV_EXCL="--prefix=" \
   ${MINGW_PREFIX}/bin/meson.exe setup \
     --prefix="${MINGW_PREFIX}" \