wolfssl: fix `-Wmissing-prototypes`

Seen with unity, H3, wolfssl with `HAVE_EX_DATA`.

Fixing:
```
lib/vtls/wolfssl.c:412:10: error: no previous prototype for function 'Curl_wssl_cache_session' [-Wmissing-prototypes]
  412 | CURLcode Curl_wssl_cache_session(struct Curl_cfilter *cf,
      |          ^
lib/vtls/wolfssl.c:412:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
  412 | CURLcode Curl_wssl_cache_session(struct Curl_cfilter *cf,
      | ^
      | static
1 error generated.
```

Follow-up to cc5c1553fbdb8c1391d0cf81134583ee32da64d4 #19852

Closes #21392

diff --git a/lib/vtls/wolfssl.h b/lib/vtls/wolfssl.h
index 778002840da93dbf643325b845612c8c991d7ce0..2490bf3e9cffeda9a97283d5f0e8820a8981254b 100644 (file)
--- a/lib/vtls/wolfssl.h
+++ b/lib/vtls/wolfssl.h
@@ -29,6 +29,8 @@
 
 #include "urldata.h"
 
+#include <wolfssl/options.h>
+
 struct alpn_spec;
 struct ssl_peer;
 struct Curl_ssl_session;