openssl: PRF_KEYED_SHA1 might not be supported

The old API has been deprecated with OpenSSL 3 and direct access to the
state isn't possible via EVP API.  In the future we might just remove this
implementation but we'd probably have to implement EAP-AKA' first, which
uses HMAC-SHA-256 with IKEv2's prf+ construct to derive keys instead
of this weird construct (plus what fips-prf builds around it) that's used
by EAP-AKA.

src/libstrongswan/plugins/openssl/openssl_plugin.c

@@ -615,7 +615,8 @@ METHOD(plugin_t, get_features, int,
 			PLUGIN_PROVIDE(XOF, XOF_SHAKE_128),
 			PLUGIN_PROVIDE(XOF, XOF_SHAKE_256),
 #endif
-#ifndef OPENSSL_NO_SHA1
+#if !defined(OPENSSL_NO_SHA1) && \
+	(OPENSSL_VERSION_NUMBER < 0x30000000L || !defined(OPENSSL_NO_DEPRECATED))
 		/* keyed sha1 hasher (aka prf) */
 		PLUGIN_REGISTER(PRF, openssl_sha1_prf_create),
 			PLUGIN_PROVIDE(PRF, PRF_KEYED_SHA1),