None of the other /proc/meminfo lines have a space in the identifier.  This
post-2.6.17 addition has the potential to break existing parsers, so use an
underscore instead (like Committed_AS).

Cc: Christoph Lameter <clameter@engr.sgi.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>