Add missing migration_guide API mappings.

Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Paul Dale <pauli@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/15732)

doc/man7/migration_guide.pod

@@ -581,6 +581,14 @@ L<ASN1_item_d2i_bio(3)>, L<ASN1_item_sign(3)> and L<ASN1_item_verify(3)>
 
 =item -
 
+L<BIO_new(3)>
+
+=item -
+
+b2i_RSA_PVK_bio() and i2b_PVK_bio()
+
+=item -
+
 L<BN_CTX_new(3)> and L<BN_CTX_secure_new(3)>
 
 =item -
@@ -627,6 +635,10 @@ L<EVP_PBE_CipherInit(3)>, L<EVP_PBE_find(3)> and L<EVP_PBE_scrypt(3)>
 
 =item -
 
+L<PKCS5_PBE_keyivgen(3)>
+
+=item -
+
 L<EVP_PKCS82PKEY(3)>
 
 =item -
@@ -705,6 +717,14 @@ L<SMIME_write_ASN1(3)>
 
 =item -
 
+L<SSL_load_client_CA_file(3)>
+
+=item -
+
+L<SSL_CTX_new(3)>
+
+=item -
+
 L<TS_RESP_CTX_new(3)>
 
 =item -
@@ -747,6 +767,10 @@ Passing NULL will use the default library context.
 
 =item -
 
+L<BIO_new_from_core_bio(3)>
+
+=item -
+
 L<EVP_ASYM_CIPHER_fetch(3)> and L<EVP_ASYM_CIPHER_do_all_provided(3)>
 
 =item -