Added a new "--kaslr=auto" command line option for X86_64 kernels
that that are configured with CONFIG_RANDOMIZE_BASE.  When set to
"auto", the KASLR relocation value will be determined automatically
by comparing the "_stext" symbol value compiled into the vmlinux file
with the _stext symbol value stored in kdump vmcoreinfo data; on live
systems the comparison will be made with the "_stext" symbol value
that is found in /proc/kallsyms.
(ahonig@google.com, anderson@redhat.com)