Add support for storing compressed logs

If log_store_compressed is set, fio won't decompress for storing
them in a file. Instead, you can use --inflate-log=logfile.fz to
output the contents to stdout.

Signed-off-by: Jens Axboe <axboe@fb.com>
diff --git a/thread_options.h b/thread_options.h
index deb3d67..e545a8f 100644
--- a/thread_options.h
+++ b/thread_options.h
@@ -110,6 +110,7 @@
 	unsigned int log_avg_msec;
 	unsigned int log_offset;
 	unsigned int log_gz;
+	unsigned int log_gz_store;
 	unsigned int norandommap;
 	unsigned int softrandommap;
 	unsigned int bs_unaligned;
@@ -339,6 +340,7 @@
 	uint32_t log_avg_msec;
 	uint32_t log_offset;
 	uint32_t log_gz;
+	uint32_t log_gz_store;
 	uint32_t norandommap;
 	uint32_t softrandommap;
 	uint32_t bs_unaligned;