[PATCH] bs= and bsrange= takes both read and write sizes

Get rid of read_bs/write_bs and read_bsrange/write_bsrange. It was ugly
and too complicated. Instead support giving both values in a single bs=
or bsrange= seperated by a comma.

Example: bs=1k,4k will use 1k blocks for reads, 4k blocks for writes.
	 bs=32k will use 32k blocks for both reads and writes.

Similar for bsrange=

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/parse.h b/parse.h
index 563712e..9b34de9 100644
--- a/parse.h
+++ b/parse.h
@@ -23,6 +23,8 @@
 	enum fio_opt_type type;
 	unsigned int off1;
 	unsigned int off2;
+	unsigned int off3;
+	unsigned int off4;
 	unsigned int max_val;
 	void *cb;
 };