intel_gpu_dump: Give a nicer message for missing batchbuffer-dumping code
intel_gpu_dump: Give a nicer message for missing batchbuffer-dumping code

This is the case where debugfs is mounted, the dri/0 directory
exists but there's no i915_ringbuffer_info file. Point the user
toward upgrading the driver.

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