Fix inline build failure

After the recent change to use ossl_inline, builds were failing on some
platforms due to a missing usage of "inline".

Reviewed-by: Richard Levitte <levitte@openssl.org>
diff --git a/ssl/statem/statem_clnt.c b/ssl/statem/statem_clnt.c
index 733a683..e7c9413 100644
--- a/ssl/statem/statem_clnt.c
+++ b/ssl/statem/statem_clnt.c
@@ -164,7 +164,7 @@
 # include <openssl/engine.h>
 #endif
 
-static inline int cert_req_allowed(SSL *s);
+static ossl_inline int cert_req_allowed(SSL *s);
 static int key_exchange_expected(SSL *s);
 static int ssl_set_version(SSL *s);
 static int ca_dn_cmp(const X509_NAME *const *a, const X509_NAME *const *b);
@@ -179,7 +179,7 @@
  *  1: Yes
  *  0: No
  */
-static inline int cert_req_allowed(SSL *s)
+static ossl_inline int cert_req_allowed(SSL *s)
 {
     /* TLS does not like anon-DH with client cert */
     if ((s->version > SSL3_VERSION