libtelnet: Make encryption decls compatible with C23.

[Collin Funk]

I've applied the attached patch to fix the following error building
libtelnet. I think the only ones remaining are in telnet/*. Once I fix
that maybe these are good for an existing CI job?

$ ./configure CC="gcc-14.1" CFLAGS="-std=c23 -Wstrict-prototypes" 
--enable-authentication --enable-encryption --with-krb5

encrypt.c:208:40: error: initialization of 'Encryptions * (*)(void)' from 
incompatible pointer type 'Encryptions * (*)(int)' 
[-Wincompatible-pointer-types]
  208 |   {{0}, 0, DIR_ENCRYPT, &encrypt_mode, findencryption},
      |                                        ^~~~~~~~~~~~~~
encrypt.c:208:40: note: (near initialization for 'ki[0].getcrypt')
encrypt.c:209:40: error: initialization of 'Encryptions * (*)(void)' from 
incompatible pointer type 'Encryptions * (*)(int)' 
[-Wincompatible-pointer-types]
  209 |   {{0}, 0, DIR_DECRYPT, &decrypt_mode, finddecryption},
      |                                        ^~~~~~~~~~~~~~
encrypt.c:209:40: note: (near initialization for 'ki[1].getcrypt')
encrypt.c: In function 'encrypt_keyid':
encrypt.c:777:9: error: too many arguments to function 'kp->getcrypt'
  777 |   ep = (*kp->getcrypt) (*kp->modep);
      |        ~^~~~~~~~~~~~~~

Collin

0001-libtelnet-Make-encryption-decls-compatible-with-C23.patch
Description: Text Data