patch 8.0.1650: too many #ifdefs

Problem:    Too many #ifdefs.
Solution:   Graduate FEAT_LISTCMDS, no reason to leave out buffer commands.
diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 6845be5..e13d34c 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -3745,10 +3745,8 @@
 		fname_case(sfname, 0);   /* set correct case for sfname */
 #endif
 
-#ifdef FEAT_LISTCMDS
 	if ((flags & ECMD_ADDBUF) && (ffname == NULL || *ffname == NUL))
 	    goto theend;
-#endif
 
 	if (ffname == NULL)
 	    other_file = TRUE;
@@ -3830,9 +3828,7 @@
      */
     if (other_file)
     {
-#ifdef FEAT_LISTCMDS
 	if (!(flags & ECMD_ADDBUF))
-#endif
 	{
 	    if (!cmdmod.keepalt)
 		curwin->w_alt_fnum = curbuf->b_fnum;
@@ -3844,7 +3840,6 @@
 	    buf = buflist_findnr(fnum);
 	else
 	{
-#ifdef FEAT_LISTCMDS
 	    if (flags & ECMD_ADDBUF)
 	    {
 		linenr_T	tlnum = 1L;
@@ -3858,7 +3853,6 @@
 		(void)buflist_new(ffname, sfname, tlnum, BLN_LISTED);
 		goto theend;
 	    }
-#endif
 	    buf = buflist_new(ffname, sfname, 0L,
 		    BLN_CURBUF | ((flags & ECMD_SET_HELP) ? 0 : BLN_LISTED));
 
@@ -4016,11 +4010,7 @@
     }
     else /* !other_file */
     {
-	if (
-#ifdef FEAT_LISTCMDS
-		(flags & ECMD_ADDBUF) ||
-#endif
-		check_fname() == FAIL)
+	if ((flags & ECMD_ADDBUF) || check_fname() == FAIL)
 	    goto theend;
 
 	oldbuf = (flags & ECMD_OLDBUF);