cgen: do not generate `_vinit()` for translated .o code

vlib/v/gen/c/cgen.v

@@ -4717,7 +4717,7 @@ fn (g &Gen) checker_bug(s string, pos token.Pos) {
 }
 
 fn (mut g Gen) write_init_function() {
-	if g.pref.no_builtin {
+	if g.pref.no_builtin || (g.pref.translated && g.pref.is_o) {
 		return
 	}
 	util.timing_start(@METHOD)

vlib/v/markused/markused.v

@@ -13,6 +13,7 @@ pub fn mark_used(mut table ast.Table, pref &pref.Preferences, ast_files []&ast.F
 	defer {
 		util.timing_measure(@METHOD)
 	}
+	// Functions that must be generated and can't be skipped
 	mut all_fn_root_names := [
 		'main.main',
 		'__new_array',