igt/gem_pwrite: Also test surfaces larger than the GTT
igt/gem_pwrite: Also test surfaces larger than the GTT

Go big or go home!

Signed-off-by: Chris Wilson <711c73f64afdce07b7e38039a96d2224209e9a6c@chris-wilson.co.uk>

chenxianqin/intel-gpu-tools,tiagovignatti/intel-gpu-tools,dlespiau/checkmate-test-igt,dlespiau/checkmate-test-igt,dlespiau/checkmate-test-igt,dlespiau/checkmate-test-igt,mv0/intel-gpu-tools,tiagovignatti/intel-gpu-tools,mv0/intel-gpu-tools,chenxianqin/intel-gpu-tools,tiagovignatti/intel-gpu-tools,mv0/intel-gpu-tools,mv0/intel-gpu-tools,chenxianqin/intel-gpu-tools,chenxianqin/intel-gpu-tools,tiagovignatti/intel-gpu-tools