Bump libvlccore revision for 1.1.6

(However it seems libvlc was not changed since 1.1.5)

src/Makefile.am

@@ -202,7 +202,7 @@ libvlccore_la_CFLAGS = `$(VLC_CONFIG) --cflags libvlccore` \
 libvlccore_la_LDFLAGS = `$(VLC_CONFIG) --ldflags libvlccore` $(AM_LDFLAGS) \
 	-no-undefined \
 	-export-symbols $(srcdir)/libvlccore.sym \
-	-version-info 4:1:0
+	-version-info 4:2:0
 libvlccore_la_LIBADD = `$(VLC_CONFIG) -libs libvlccore` $(AM_LIBADD) \
 	$(LTLIBINTL) ../compat/libcompat.la
 libvlccore_la_DEPENDENCIES = libvlccore.sym