[Crash-utility] [crash-utility][ARM64][patch] Auto calculate kimage_voffset by kaslr offset

Hi Dave, In my develop enviroment, kaslr offset will be stored in SoC on-chip memory for debuging, but crash utility is not work if i only set kaslr offset by command '--kaslr XXX', it also need correct kimage_voffset. error message without the patch: VA_BITS: 39 using 40000000 as phys_offset kimage_voffset: 0 phys_offset: 40000000 .....cut.... <readmem: ffffff9381e074a0, KVADDR, "cpu_possible_mask", 8, (FOE), 7fffce0dfa48> <read_ramdump: addr: ffffff9381e074a0 paddr: 13b9e074a0 cnt: 8> read_ramdump: READ_ERROR: offset not found for paddr: 13b9e074a0 crash: read error: kernel virtual address: ffffff9381e074a0 type: "cpu_possible_mask" This patch add a function to auto calculate kimage_voffset by kaslr offset. Please review it. Thanks, Yueyi Li