[pangomm] Link to the glibmm-2.52 version of glibmm_generate_extra_defs.

[Murray Cumming <murrayc src gnome org>]

commit 50dba58213b09c2e48c2146351e6b3f10f3c4b2a
Author: Murray Cumming <murrayc murrayc com>
Date:   Tue Nov 15 21:17:21 2016 +0100

    Link to the glibmm-2.52 version of glibmm_generate_extra_defs.

 tools/Makefile.am |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/tools/Makefile.am b/tools/Makefile.am
index f8f2f2f..41026d4 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -30,7 +30,7 @@ dist_noinst_DATA = README
 noinst_PROGRAMS  = extra_defs_gen/generate_extra_defs
 
 extra_defs_gen_generate_extra_defs_SOURCES = extra_defs_gen/generate_defs_pango.cc
-extra_defs_gen_generate_extra_defs_LDADD   = $(PANGOMM_LIBS) -lglibmm_generate_extra_defs-2.4
+extra_defs_gen_generate_extra_defs_LDADD   = $(PANGOMM_LIBS) -lglibmm_generate_extra_defs-2.52
 extra_defs_gen_generate_extra_defs_LDFLAGS = -no-undefined -avoid-version
 
 AM_CPPFLAGS = -I$(top_builddir) $(GTHREAD_CFLAGS) $(PANGOMM_CFLAGS)