x86: Remove asm/apicnum.h

arch/x86/include/asm/apicnum.h is not referenced anywhere
anymore. Its definitions appear in apicdef.h. Remove it.

Signed-off-by: Dimitri Sivanich <sivanich@sgi.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Acked-by: Mike Travis <travis@sgi.com>
LKML-Reference: <20091110195835.GA4393@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>