configure.ac: Fix loongson-mmi out-of-tree builds

When building out-of-tree, gcc wasn't able to find loongson-mmintrin.h
to compile the test program. Add -I$srcdir to CFLAGS to point gcc to it.

diff --git a/configure.ac b/configure.ac
index 345bc33..57fd060 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -281,7 +281,7 @@ have_loongson_mmi=no
 AC_MSG_CHECKING(whether to use Loongson MMI)
 
 xserver_save_CFLAGS=$CFLAGS
-CFLAGS=" $LS_CFLAGS $CFLAGS"
+CFLAGS=" $LS_CFLAGS $CFLAGS -I$srcdir"
 AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #ifndef __mips_loongson_vector_rev
 #error "Loongson Multimedia Instructions are only available on Loongson"