Fix the parameter types of the CRYPTO_EX_dup function type.

This fixes a strict aliasing issue in ui_dup_method_data.

The parameter type of CRYPTO_EX_dup's from_d parameter
is in fact void **, since it points to a pointer.

This function is rarely used, therefore fix the param type
although that may be considered an API breaking change.

Reviewed-by: Richard Levitte <levitte@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/2986)
