st/clover: Fix build after shrink of pipe_box

Fixes: 3dfe61e ("gallium: decrease the size of pipe_box - 24 -> 16 bytes")
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=100569
Signed-off-by: Aaron Watry <awatry@gmail.com>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Tested-by: Vinson Lee <vlee@freedesktop.org>

src/gallium/state_trackers/clover/core/resource.cpp

@@ -33,9 +33,9 @@ namespace {
    class box {
    public:
       box(const resource::vector &origin, const resource::vector &size) :
-         pipe({ (int)origin[0], (int)origin[1],
-                (int)origin[2], (int)size[0],
-                (int)size[1], (int)size[2] }) {
+        pipe({ (int)origin[0], (int16_t)origin[1],
+               (int16_t)origin[2], (int)size[0],
+               (int16_t)size[1], (int16_t)size[2] }) {
       }
 
       operator const pipe_box *() {