[PATCH] Improve io logging

write_iolog was broken. Change iolog= to read_iolog= to keep things
nicely seperated.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fio.h b/fio.h
index 046171a..d8b0152 100644
--- a/fio.h
+++ b/fio.h
@@ -222,13 +222,13 @@
 	os_cpu_mask_t cpumask;
 	unsigned int iolog;
 	unsigned int read_iolog;
-	unsigned int write_iolog;
 	unsigned int rwmixcycle;
 	unsigned int rwmixread;
 	unsigned int rwmixwrite;
 	unsigned int nice;
 
-	char *iolog_file;
+	char *read_iolog_file;
+	char *write_iolog_file;
 	void *iolog_buf;
 	FILE *iolog_f;