[gnome-desktop] build: Fix syntax highlighting in configure.ac

[Bastien Nocera <hadess src gnome org>]

commit 2bf09a04e3ebf91ab8375269acecd8f268766ffd
Author: Bastien Nocera <hadess hadess net>
Date:   Fri Jul 21 00:15:11 2017 +0200

    build: Fix syntax highlighting in configure.ac

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 2181b17..fe4f166 100644
--- a/configure.ac
+++ b/configure.ac
@@ -131,7 +131,7 @@ PKG_CHECK_MODULES(XLIB, x11,
     [X11_PACKAGE=
      AC_PATH_XTRA
      if test "x$no_x" = xyes; then
-       AC_MSG_ERROR("no (requires X development libraries)")
+       AC_MSG_ERROR(["no (requires X development libraries)"])
      else
        XLIB_LIBS="$X_PRE_LIBS $X_LIBS -lX11 $X_EXTRA_LIBS"
        XLIB_CFLAGS=$X_CFLAGS