tools lib traceevent: Add support for __print_hex()

Since the __print_hex() function is used in print fmt now, add
corresponding parser routines. This makes the output of perf script on
the kvm_emulate_insn event not to fail any more.

 before:
      kvm_emulate_insn:     [FAILED TO PARSE] rip=3238197797 ...

 after:
      kvm_emulate_insn:     0:c102fa25:89 10 (prot32)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1340757701-10711-4-git-send-email-namhyung@kernel.org


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>