POLARSSL_CIPHER_ID_3DES never used

[evvliet]

In include/polarssl/cipher.h a cipher_id_t value is defined for POLARSSL_CIPHER_ID_3DES but it is actually never used.
I would have expected it to be used in library/cipher_wrap.c by des_ede3_info but that uses POLARSSL_CIPHER_ID_DES instead.

I'm not entirely sure if it can safely be omitted (from the header file) or changed. If not, it might be convenient to mark it as /* Unused! */.

[mpg]

Good catch. I'll mark it as unused in the 1.3 branch, and change des_ede3_info to use it in the 2.0 branch. Thanks for your report.