kdump: report actual value of VMCOREINFO_OSRELEASE in VMCOREINFO

The current implementation reports the structure name as
VMCOREINFO_OSRELEASE in VMCOREINFO, e.g.

        VMCOREINFO_OSRELEASE=init_uts_ns.name.release

That doesn't make sense because it's always the same. Instead, use the
value, e.g.

        VMCOREINFO_OSRELEASE=2.6.26-rc3

That's also what the 'makedumpfile -g' does.

Signed-off-by: Bernhard Walle <bwalle@suse.de>
Cc: "Ken'ichi Ohmichi" <oomichi@mxs.nes.nec.co.jp>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>