[gnome-session] build: Don't link against libgconf when --disable-gconf was passed

[Ray Strode <halfline src gnome org>]

commit 453b18dffc83435ce22d76e909d68e75ea35febb
Author: Marvin Schmidt <marv exherbo org>
Date:   Sat May 20 22:12:54 2017 +0200

    build: Don't link against libgconf when --disable-gconf was passed
    
    Calling `PKG_CHECK_MODULES([GCONF], ...)` unconditionally lead to
    GCONF_{CFLAGS,LIBS} being set whenever GConf was present. This had the
    effect that gnome-session-binary was linked against libgconf even when
    `--disable-gconf` was passed
    
    https://bugzilla.gnome.org/show_bug.cgi?id=783007

 configure.ac |   16 ++++++++--------
 1 files changed, 8 insertions(+), 8 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index ec47045..53002aa 100644
--- a/configure.ac
+++ b/configure.ac
@@ -96,16 +96,16 @@ AC_ARG_ENABLE([gconf],
               [enable_gconf=$enableval],
               [enable_gconf=auto])
 
-PKG_CHECK_MODULES(GCONF, gconf-2.0, [have_gconf=yes], [have_gconf=no])
+if test x$enable_gconf != xno ; then
+        PKG_CHECK_MODULES(GCONF, gconf-2.0, [have_gconf=yes], [have_gconf=no])
 
-if test x$enable_gconf = xauto ; then
-        enable_gconf=$have_gconf
-elif test x$enable_gconf = xyes -a x$have_gconf = xno ; then
-        AC_MSG_ERROR([GConf support explicitly required, but gconf not found])
-fi
+        if test x$enable_gconf = xyes -a x$have_gconf = xno ; then
+            AC_MSG_ERROR([GConf support explicitly required, but gconf not found])
+        fi
 
-if test x$enable_gconf = xyes ; then
-        AC_DEFINE([HAVE_GCONF], [1], [Define if we support gconf-based autostart])
+        if test x$have_gconf = xyes ; then
+            AC_DEFINE([HAVE_GCONF], [1], [Define if we support gconf-based autostart])
+        fi
 fi
 
 dnl ====================================================================