fix build failures due to static allocate_key_context in pqc.

[Li-Aaron]

fix #3459

[steven-bellock]

@Li-Aaron this failure pattern exists in other files such as https://github.com/DMTF/libspdm/blob/main/os_stub/cryptlib_openssl/pk/x509.c.

[Li-Aaron]

@Li-Aaron this failure pattern exists in other files such as https://github.com/DMTF/libspdm/blob/main/os_stub/cryptlib_openssl/pk/x509.c.

Can you share me your build command for reproducing this?
I didn't find the issue in x509.c

[steven-bellock]

I didn't find the issue in x509.c

Ah, looks like that one is ok. But crypto_macro.patch will produce

/home/scratch.sbellock_sw/repo/libspdm/os_stub/cryptlib_openssl/der/der.c:60:13: error: 'allocate_key_context' defined but not used [-Werror=unused-function]
   60 | static bool allocate_key_context(EVP_PKEY *pkey, void **context)
      |             ^~~~~~~~~~~~~~~~~~~~
/home/scratch.sbellock_sw/repo/libspdm/os_stub/cryptlib_openssl/der/der.c:27:13: error: 'get_public_key_from_der_bio' defined but not used [-Werror=unused-function]
   27 | static bool get_public_key_from_der_bio(const uint8_t *der_data, size_t der_size, EVP_PKEY **pkey)