Document the raw key getter functions
Document the raw key getter functions

EVP_PKEY_get_raw_private_key() and EVP_PKEY_get_raw_public_key()

Reviewed-by: Rich Salz <c04971a99e5a9ee80eaab4b1deb37e845b0bd697@openssl.org>
Reviewed-by: Tim Hudson <eb0be8e447f673b41b10eda09d63cd72526b0a42@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/6394)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl