r600g: force full cache for hyperz

r600g: force full cache for hyperz

Seems that in some case allowing half cache usage confuse the gpu
and trigger lockup. Force full cache use.

Should fix :
https://bugs.freedesktop.org/show_bug.cgi?id=59592
https://bugs.freedesktop.org/show_bug.cgi?id=60848
https://bugs.freedesktop.org/show_bug.cgi?id=60969
https://bugs.freedesktop.org/show_bug.cgi?id=61747
https://bugs.freedesktop.org/show_bug.cgi?id=62466
https://bugs.freedesktop.org/show_bug.cgi?id=62669
https://bugs.freedesktop.org/show_bug.cgi?id=62721
https://bugs.freedesktop.org/show_bug.cgi?id=63124

Signed-off-by: Jerome Glisse <jglisse@redhat.com>