Remove unnecessary argc assign

Found by Linux Verification Center (linuxtesting.org) with SVACE.

CLA:trivial

Reviewed-by: Norbert Pocs <norbertp@openssl.org>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
MergeDate: Thu Jan  8 10:03:55 2026
(Merged from https://github.com/openssl/openssl/pull/29457)

apps/passwd.c

@@ -196,7 +196,6 @@ int passwd_main(int argc, char **argv)
     }
 
     /* All remaining arguments are the password text */
-    argc = opt_num_rest();
     argv = opt_rest();
     if (*argv != NULL) {
         if (pw_source_defined)

apps/rehash.c

@@ -550,7 +550,6 @@ int rehash_main(int argc, char **argv)
     }
 
     /* Optional arguments are directories to scan. */
-    argc = opt_num_rest();
     argv = opt_rest();
 
     evpmd = EVP_sha1();