Add missing bracket
Wasn't spotted earlier because it's guarded by `! HAVE_GETRANDOM`.
@@ -135,7 +135,7 @@ int mbedtls_platform_entropy_poll( void *data,
return( MBEDTLS_ERR_ENTROPY_SOURCE_FAILED );
/* Fall through if the system call isn't known. */
#else
- ((void) ret;
+ ((void) ret);
#endif /* HAVE_GETRANDOM */
*olen = 0;
