lib/intel_batchbuffer: Add support for custom engine layouts

Don't assume fixed engine ids and use context configuration in
intel_bb to find the appropriate engine when executing the batchbuffer.

Signed-off-by: Karolina Drobnik <karolina.drobnik@intel.com>
Reviewed-by: Zbigniew Kempczynski <zbigniew.kempczynski@intel.com>