Fix referenses in section 3 manuals

Reviewed-by: Rich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/1900)
diff --git a/doc/man3/SSL_get_rbio.pod b/doc/man3/SSL_get_rbio.pod
index 5ac4ca2..f6ae3e9 100644
--- a/doc/man3/SSL_get_rbio.pod
+++ b/doc/man3/SSL_get_rbio.pod
@@ -35,7 +35,7 @@
 
 =head1 SEE ALSO
 
-L<SSL_set_bio(3)>, L<ssl(3)> , L<bio(3)>
+L<SSL_set_bio(3)>, L<ssl(7)> , L<bio(7)>
 
 =head1 COPYRIGHT