intel/tools/error: Decode compute shaders.

intel/tools/error: Decode compute shaders.

This is a bit more annoying than your average shader - we need to look
at MEDIA_INTERFACE_DESCRIPTOR_LOAD in the batch buffer, then hop over
to the dynamic state buffer to read the INTERFACE_DESCRIPTOR_DATA, then
hop over to the instruction buffer to decode the program.

Now that we store all the buffers before decoding, we can actually do
this fairly easily.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>