perf tools: Add support for displaying event parser debug info

perf tools: Add support for displaying event parser debug info

Adding PARSER_DEBUG Makefile variable to enable building event scanner/
parser with debug enabled. This results in verbose output right out of
the scanner/parser.

It's useful for debuging the event parser. Keeping this only for event
parser so far.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1337584373-2741-3-git-send-email-jolsa@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>