vmcore-dmesg: Handle struct log to struct printk_log renaming

vmcore-dmesg has been failing for me for quite some time as struct log
was renamed to struct printk_log.

62e32ac printk: rename struct log to struct printk_log

This patch has been sitting in mailing list for quite some time. It
is time to repost the patch.

I took original patch of Lubomir and modified a bit to take care of
concern of hardcoded string length.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Signed-off-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
kexec-tools: add noefi arch cmdline option

For kernel boot with efi=old_map or some quirked machines like SGI UV
they use old ioremap instead of 1:1 mapping. But kexec efi support
depends on the 1:1 mapping thus we need to switch to use the old way

There's a kernel patch for exporting the efi flags so we can check the memory
mapping method. But user may want to explictly disable efi boot for unknown
reasons.

So here add a new arch option '--noefi' for this case.

Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>
kexec-tools: usage text fix

There's one more '-' in arch_usage, thus
s/pass--memmap-cmdline/pass-memmap-cmdline

Signed-off-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Simon Horman <horms@verge.net.au>