abuild: do not exclude depends_dev

fixes regression introduced with commit 6582be1d (abuild: pull only in
needed dependencies for -dev packages)

abuild.in

@@ -1344,7 +1344,7 @@ dbg() {
 # predefined splitfunc dev
 default_dev() {
 	local i= j=
-	depends=""
+	depends="$depends_dev"
 	pkgdesc="$pkgdesc (development files)"
 
 	cd "$pkgdir" || return 0