patch 8.2.4008: error messages are spread out

Problem:    Error messages are spread out.
Solution:   Move more error messages to errors.h.
diff --git a/src/memline.c b/src/memline.c
index b8ed03e..07b0f57 100644
--- a/src/memline.c
+++ b/src/memline.c
@@ -4415,7 +4415,7 @@
 	// Limit symlink depth to 100, catch recursive loops.
 	if (++depth == 100)
 	{
-	    semsg(_("E773: Symlink loop for \"%s\""), fname);
+	    semsg(_(e_symlink_loop_for_str), fname);
 	    return FAIL;
 	}