arm64: kdump: add VMCOREINFO's for user-space tools

arm64: kdump: add VMCOREINFO's for user-space tools

BugLink: https://bugs.launchpad.net/bugs/1694859
In addition to common VMCOREINFO's defined in
crash_save_vmcoreinfo_init(), we need to know, for crash utility,
  - kimage_voffset
  - PHYS_OFFSET
to examine the contents of a dump file (/proc/vmcore) correctly
due to the introduction of KASLR (CONFIG_RANDOMIZE_BASE) in v4.6.

  - VA_BITS
is also required for makedumpfile command.

arch_crash_save_vmcoreinfo() appends them to the dump file.
More VMCOREINFO's may be added later.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
Reviewed-by: James Morse <james.morse@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
(cherry picked from commit 20a166243328c14a0c24bd8c7919223ab4174917)
Signed-off-by: dann frazier <dann.frazier@canonical.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>