[gegl] Fix invalid shell syntax in configure.ac

[Mikael Magnusson <mikachu src gnome org>]

commit 9073a406ca5071c65953313c3152f00f24679056
Author: Mikael Magnusson <mikachu src gnome org>
Date:   Sat Nov 8 12:53:04 2014 +0100

    Fix invalid shell syntax in configure.ac

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 7f5733a..50fb060 100644
--- a/configure.ac
+++ b/configure.ac
@@ -473,7 +473,7 @@ if test "x$with_vala" != "xno"; then
     have_vapigen="no  (vapigen not found)")
 fi
 
-if test "x$have_vapigen" == "xyes"; then
+if test "x$have_vapigen" = "xyes"; then
   AC_PATH_PROG(VAPIGEN, vapigen, no)
   if test "$VAPIGEN" = "no"; then
     have_vapigen="no  (vapigen executable not found)"