Add --debug=parse for option parsing debug

Adds log.h and debug.h to split the logging and debug bits out of
fio, so that the parser can use them.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/init.c b/init.c
index 4f57ba3..6599729 100644
--- a/init.c
+++ b/init.c
@@ -812,6 +812,7 @@
 	{ .name = "blktrace",	.shift = FD_BLKTRACE },
 	{ .name = "verify",	.shift = FD_VERIFY },
 	{ .name = "random",	.shift = FD_RANDOM },
+	{ .name = "parse",	.shift = FD_PARSE },
 	{ },
 };