patch 8.2.0728: messages about a deadly signal are not left aligned

Problem:    Messages about a deadly signal are not left aligned.
Solution:   Output a CR before the NL. (Dominique Pelle, #6055)
diff --git a/src/os_unix.c b/src/os_unix.c
index 8424b11..596fb0e 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -1083,10 +1083,10 @@
 
     // No translation, it may call malloc().
 #ifdef SIGHASARG
-    sprintf((char *)IObuff, "Vim: Caught deadly signal %s\n",
+    sprintf((char *)IObuff, "Vim: Caught deadly signal %s\r\n",
 							 signal_info[i].name);
 #else
-    sprintf((char *)IObuff, "Vim: Caught deadly signal\n");
+    sprintf((char *)IObuff, "Vim: Caught deadly signal\r\n");
 #endif
 
     // Preserve files and exit.  This sets the really_exiting flag to prevent