patch 8.1.1371: cannot recover from a swap file

Problem:    Cannot recover from a swap file.
Solution:   Do not expand environment variables in the swap file name.
            Do not check the extension when we already know a file is a swap
            file.  (Ken Takata, closes 4415, closes #4369)

src/ex_docmd.c

@@ -6725,7 +6725,7 @@ ex_recover(exarg_T *eap)
 
 	    && (*eap->arg == NUL
 			     || setfname(curbuf, eap->arg, NULL, TRUE) == OK))
-	ml_recover();
+	ml_recover(TRUE);
     recoverymode = FALSE;
 }