tests/gem_media_fill: add support for gen8

v2: Fixed the source register used for the send with EOT
    Fixed the posted destination operand for the send with EOT

v3: Workaround: Insert MEDIA_STATE_FLUSH after MEDIA_OBJECT.
    Fixed the cache agent used in media_block_write message
    Set Instruction Buffer size Modify Enable to 1, otherwise it may result in GPU hang

Reviewed-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Xiang, Haihao <haihao.xiang@intel.com>
5 files changed