readconf.c: Avoid a xstrdup

[Martin Vahlensieck]

Hi

There is no need to duplicate options->send_env[i] only free it
in all cases.  Just use options->send_env[i] directly.

Best,

Martin

Index: readconf.c
===================================================================
RCS file: /cvs/src/usr.bin/ssh/readconf.c,v
retrieving revision 1.366
diff -u -p -r1.366 readconf.c
--- readconf.c  8 Feb 2022 08:59:12 -0000       1.366
+++ readconf.c  19 Apr 2022 09:38:48 -0000
@@ -740,19 +740,15 @@ static void
 rm_env(Options *options, const char *arg, const char *filename, int linenum)
 {
        int i, j, onum_send_env = options->num_send_env;
-       char *cp;
 
        /* Remove an environment variable */
        for (i = 0; i < options->num_send_env; ) {
-               cp = xstrdup(options->send_env[i]);
-               if (!match_pattern(cp, arg + 1)) {
-                       free(cp);
+               if (!match_pattern(options->send_env[i], arg + 1)) {
                        i++;
                        continue;
                }
                debug3("%s line %d: removing environment %s",
-                   filename, linenum, cp);
-               free(cp);
+                   filename, linenum, options->send_env[i]);
                free(options->send_env[i]);
                options->send_env[i] = NULL;
                for (j = i; j < options->num_send_env - 1; j++) {