x86, boot: Removed unused debug flag and set code

x86, boot: Removed unused debug flag and set code

As we're no longer using the flag we don't need to extract the value from the
command line and store it. This is a step towards removing command line
parameter code.

Signed-off-by: Joe Millenbach <jmillenbach@gmail.com>
Link: http://lkml.kernel.org/r/1342746282-28497-6-git-send-email-jmillenbach@gmail.com
Signed-off-by: Gokul Caushik <caushik1@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>