Fix unamalgamated build

mongoose.c

@@ -5227,6 +5227,7 @@ long mg_tls_send(struct mg_connection *c, const void *buf, size_t len) {
 #endif
 
 
+
 #if MG_ENABLE_OPENSSL
 static int mg_tls_err(struct mg_tls *tls, int res) {
   int err = SSL_get_error(tls->ssl, res);

src/tls_openssl.c

@@ -1,3 +1,4 @@
+#include "fmt.h"
 #include "tls.h"
 
 #if MG_ENABLE_OPENSSL