Libcompat: Swap CXX/CFLAGS.

This is the same as done for the native build in r300770 to ensure that
the libc++ build reads from SYSROOT/usr/include/c++/v1 before reading
from SYSROOT/usr/include.

Makefile.libcompat

@@ -92,7 +92,7 @@ LIBCOMPATWMAKEENV+= MAKEOBJDIRPREFIX=${LIBCOMPAT_OBJTREE} \
 LIBCOMPATWMAKEENV+=	BUILD_TOOLS_META=.NOMETA_CMP
 .endif
 LIBCOMPATWMAKEFLAGS+= CC="${XCC} ${LIBCOMPATCFLAGS}" \
-		CXX="${XCXX} ${LIBCOMPATCFLAGS} ${LIBCOMPATCXXFLAGS}" \
+		CXX="${XCXX} ${LIBCOMPATCXXFLAGS} ${LIBCOMPATCFLAGS}" \
 		CPP="${XCPP} ${LIBCOMPATCFLAGS}" \
 		DESTDIR=${LIBCOMPATTMP} \
 		-DNO_CPU_CFLAGS \