assembler: Make sure nobody adds a field back to struct brw_instruction
assembler: Make sure nobody adds a field back to struct brw_instruction

Adding something there will break the library, so we might as check for
it.

Signed-off-by: Damien Lespiau <64bd3cb94f359c1a3ce68dae5e26b40578526277@intel.com>

erikarn/intel-gpu-tools,dlespiau/checkmate-test-igt,mv0/intel-gpu-tools,ChrisCummins/intel-gpu-tools,chenxianqin/intel-gpu-tools,tiagovignatti/intel-gpu-tools,yipdw/intel-gpu-tools,yipdw/intel-gpu-tools,ChrisCummins/intel-gpu-tools,erikarn/intel-gpu-tools,ChrisCummins/intel-gpu-tools,tiagovignatti/intel-gpu-tools,erikarn/intel-gpu-tools,chenxianqin/intel-gpu-tools,tiagovignatti/intel-gpu-tools,mv0/intel-gpu-tools,tiagovignatti/intel-gpu-tools,dlespiau/checkmate-test-igt,yipdw/intel-gpu-tools,ChrisCummins/intel-gpu-tools,dlespiau/checkmate-test-igt,dlespiau/checkmate-test-igt,chenxianqin/intel-gpu-tools,mv0/intel-gpu-tools,rib/intel-gpu-tools,yipdw/intel-gpu-tools,mv0/intel-gpu-tools,rib/intel-gpu-tools,rib/intel-gpu-tools,chenxianqin/intel-gpu-tools,rib/intel-gpu-tools,erikarn/intel-gpu-tools