net.openssl: add manual .str() methods for C.SSL and C.SSL_CTX, fix a bug in the V auto str generation as well.

vlib/net/openssl/openssl_compiles_test.v

@@ -1,5 +1,16 @@
 import net.openssl
 
+struct Abc {
+	x &C.SSL_CTX
+}
+
+fn test_printing_struct_with_reference_field_of_type_ssl_ctx() {
+	a := Abc{&C.SSL_CTX(123)}
+	dump(a)
+	sa := a.str()
+	assert sa.contains('&C.SSL_CTX(0x7b)')
+}
+
 fn test_openssl_compiles() {
 	assert openssl.is_used == 1
 	assert true