Fix bracket style

Signed-off-by: Guilhem Bryant <Guilhem.Bryant@arm.com>
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index 4a8686c..c0ebfcb 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -1853,11 +1853,13 @@
 
     if( mbedtls_ssl_get_psk( ssl, &psk, &psk_len )
             == MBEDTLS_ERR_SSL_PRIVATE_KEY_REQUIRED )
+    {
         /*
          * This should never happen because the existence of a PSK is always
          * checked before calling this function
          */
         MBEDTLS_SSL_DEBUG_MSG( 1, ( "should never happen" ) );
+    }
 
     /*
      * PMS = struct {