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/RSA_get0_key.pod b/doc/man3/RSA_get0_key.pod
index 52f83e1..557eb43 100644
--- a/doc/man3/RSA_get0_key.pod
+++ b/doc/man3/RSA_get0_key.pod
@@ -90,7 +90,7 @@
 
 =head1 SEE ALSO
 
-L<rsa(3)>, L<RSA_new(3)>, L<RSA_size(3)>
+L<RSA_new(3)>, L<RSA_size(3)>
 
 =head1 HISTORY