[empathy] Fix AC_ARG_ENABLE usage

[Guillaume Desmottes <gdesmott src gnome org>]

commit c40cc8f6d6510b66f774c70097e0d19ee933f783
Author: Sjoerd Simons <sjoerd simons collabora co uk>
Date:   Mon Sep 3 13:33:13 2012 +0200

    Fix AC_ARG_ENABLE usage

 configure.ac |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 3eea283..c8b9355 100644
--- a/configure.ac
+++ b/configure.ac
@@ -221,10 +221,12 @@ PKG_CHECK_MODULES(EMPATHY,
 # -----------------------------------------------------------
 AC_ARG_ENABLE(gst-1.0,
               AS_HELP_STRING([--enable-gst-1.0=@<:@no/yes/auto@:>@],
-                             [build with GStreamer 1.0]), enable_gst1=yes,
+                             [build with GStreamer 1.0]),
+                             enable_gst1=$enableval,
                              enable_gst1=auto)
 
 # Try to use GStreamer 1.Ã if available
+have_gst1="no"
 if test "x$enable_gst1" != "xno"; then
   PKG_CHECK_MODULES(EMPATHY_CALL,
   [