patch 8.2.4148: deleting any mapping may cause <ScritpCmd> to fail

Problem:    Deleting any mapping may cause <ScritpCmd> to not set the script
            context.
Solution:   Only reset last_used_map if it is the deleted mapping.
            (closes #9568)
diff --git a/src/map.c b/src/map.c
index f16397a..ff117dc 100644
--- a/src/map.c
+++ b/src/map.c
@@ -86,7 +86,7 @@
     *mpp = mp->m_next;
     vim_free(mp);
 #ifdef FEAT_EVAL
-    reset_last_used_map();
+    reset_last_used_map(mp);
 #endif
 }