exa2pro/starpu-max: porting work to Maxeler DFE @ d341e82c305be6bcdfcda5e2fffc5d69867a3746

Samuel Thibault 86bec59609 This test should work now		11 lat temu
..
disk_compute.c	aba9b7562b Make disk test actually test all backends. Partly revert r13785 which was using a union as a structure.	11 lat temu
disk_copy.c	7b2bbc9659 Use powers of two so that o_direct can work	11 lat temu
disk_pack.c	86bec59609 This test should work now	11 lat temu