x86/idt: Remove the tracing IDT leftovers

Stephen reported a merge conflict with the XEN tree. That also shows that the
IDT cleanup forgot to remove the now unused trace_{trap} defines.

Remove them.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Juergen Gross <jgross@suse.com>