tracing/irq: convert irq traces to use TRACE_EVENT macro

The TRACE_FORMAT will soon be deprecated. This patch converts it to
the TRACE_EVENT macro.

Note, this change should also speed up the tracing.

[ Impact: remove a user of deprecated TRACE_FORMAT ]

Cc: Jason Baron <jbaron@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>