patch 8.2.2225: Vim9: error when using :import in legacy script twice

Problem:    Vim9: error when using :import in legacy script twice.
Solution:   Make it possible to redefine an import when reloading.
diff --git a/src/vim9compile.c b/src/vim9compile.c
index baf7923..bd530b1 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -2416,7 +2416,7 @@
     import = find_imported(name, 0, cctx);
     if (import != NULL)
     {
-	if (import->imp_all)
+	if (import->imp_flags & IMP_FLAGS_STAR)
 	{
 	    char_u	*p = skipwhite(*end);
 	    char_u	*exp_name;