[gimp] app: fix gimp-scratch linking

[Ell <ell src gnome org>]

commit ae6bebb9815fc3dad76efba5dd1b09c403c604e7
Author: Ell <ell_se yahoo com>
Date:   Sat Dec 1 06:21:59 2018 -0500

    app: fix gimp-scratch linking

 app/Makefile.am | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/app/Makefile.am b/app/Makefile.am
index cb7f8f61b0..8ce4c621ba 100644
--- a/app/Makefile.am
+++ b/app/Makefile.am
@@ -149,7 +149,8 @@ AM_LDFLAGS = \
        -Wl,-u,$(SYMPREFIX)gimp_layer_mode_is_legacy            \
        -Wl,-u,$(SYMPREFIX)gimp_parallel_init                   \
        -Wl,-u,$(SYMPREFIX)gimp_async_set_new                   \
-       -Wl,-u,$(SYMPREFIX)gimp_uncancelable_waitable_new
+       -Wl,-u,$(SYMPREFIX)gimp_uncancelable_waitable_new       \
+       -Wl,-u,$(SYMPREFIX)gimp_scratch_block_new
 
 gimpconsoleldadd = \
        xcf/libappxcf.a                                         \