package libgda: disable postgresql support

I doubt this ever worked, it doesn't detect the prefixed pg_config and doesn't seem to support postgresql 9+

src/libgda.mk

@@ -8,7 +8,7 @@ $(PKG)_CHECKSUM := 61d0b498202b780750633cc2e957c40325d6c705
 $(PKG)_SUBDIR   := libgda-$($(PKG)_VERSION)
 $(PKG)_FILE     := libgda-$($(PKG)_VERSION).tar.xz
 $(PKG)_URL      := http://ftp.gnome.org/pub/gnome/sources/libgda/$(call SHORT_PKG_VERSION,$(PKG))/$($(PKG)_FILE)
-$(PKG)_DEPS     := gcc glib libxml2 mdbtools postgresql
+$(PKG)_DEPS     := gcc glib libxml2 mdbtools
 
 define $(PKG)_UPDATE
     echo 'TODO: Updates for package libgda need to be fixed.' >&2;
@@ -26,6 +26,7 @@ define $(PKG)_BUILD
         --disable-gtk-doc \
         --without-bdb \
         --with-mdb \
+        --without-postgres \
         --without-oracle \
         --without-mysql \
         --without-firebird \