Wrap more of ocspapitest.c in OPENSSL_NO_OCSP

make_dummy_resp() uses OCSP types, and get_cert_and_key() is unused
once make_dummy_resp() is compiled out, so neither can be included
in the build when OCSP is disabled and strict warnings are active.

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/4873)
diff --git a/test/ocspapitest.c b/test/ocspapitest.c
index aa477a8..43b03e3 100644
--- a/test/ocspapitest.c
+++ b/test/ocspapitest.c
@@ -21,6 +21,7 @@
 static const char *certstr;
 static const char *privkeystr;
 
+#ifndef OPENSSL_NO_OCSP
 static int get_cert_and_key(X509 **cert_out, EVP_PKEY **key_out)
 {
     BIO *certbio, *keybio;
@@ -86,7 +87,6 @@
     return bs_out;
 }
 
-#ifndef OPENSSL_NO_OCSP
 static int test_resp_signer(void)
 {
     OCSP_BASICRESP *bs = NULL;