engine: Fix compile error on Fedora 40

[ifranzki]

ibmca_pkey.c:627:47: error: passing argument 2 of 'EVP_PKEY_meth_set_copy' from incompatible pointer type [-Wincompatible-pointer-types]
      627 |     EVP_PKEY_meth_set_copy(ibmca_ed448_pmeth, ibmca_ed448_copy);