[gimp] configure: fix a PKG_CHECK_MODULES() test.

[Jehan Pagès <jehanp src gnome org>]

commit 68e15ad8c51b36630db31220d981435f0de2e972
Author: Jehan <jehan girinstud io>
Date:   Sat Apr 8 18:04:22 2017 +0200

    configure: fix a PKG_CHECK_MODULES() test.
    
    s/gtk+2.0/gtk+-2.0/ for the test for recommended GTK+ version on
    Window.

 configure.ac |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 6d5d442..67be213 100644
--- a/configure.ac
+++ b/configure.ac
@@ -736,7 +736,7 @@ AC_MSG_RESULT($have_gtk_2_26)
 # See bugs 769550 and 781020.
 have_recommended_gtk=""
 if test "x$platform_win32" = "xyes"; then
-    PKG_CHECK_MODULES(RECOMMENDED_WIN32_GTK, gtk+2.0 >= gtk_win32_recommended_version,
+    PKG_CHECK_MODULES(RECOMMENDED_WIN32_GTK, gtk+-2.0 >= gtk_win32_recommended_version,
                       have_recommended_gtk="yes", have_recommended_gtk="no")
 
     if test "x$have_recommended_gtk" = xno; then