Fix cosmetic nit when printing out "override $mode" and "$owner/$group ..."

The wrong index was being checked for == ' ' in the resulting stringified
mode from strmode(3) -- it should have been the 11th value, not the 10th.

MFC after:	3 days
PR:		76711
Submitted by:	Vasil Dimov <vd@datamax.bg>

bin/rm/rm.c

@@ -515,7 +515,7 @@ check(const char *path, const char *name, struct stat *sp)
 			    "%s: -P was specified, but file is not writable",
 			    path);
 		(void)fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ",
-		    modep + 1, modep[9] == ' ' ? "" : " ",
+		    modep + 1, modep[10] == ' ' ? "" : " ",
 		    user_from_uid(sp->st_uid, 0),
 		    group_from_gid(sp->st_gid, 0),
 		    *flagsp ? flagsp : "", *flagsp ? " " : "",