bio-integrity: Add explicit field for owner of bip_buf

This was the only real user of BIO_CLONED, which didn't have very clear
semantics. Convert to its own flag so we can get rid of BIO_CLONED.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 794bcd0..ef24466 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -187,6 +187,7 @@
 	unsigned short		bip_slab;	/* slab the bip came from */
 	unsigned short		bip_vcnt;	/* # of integrity bio_vecs */
 	unsigned short		bip_idx;	/* current bip_vec index */
+	unsigned		bip_owns_buf:1;	/* should free bip_buf */
 
 	struct work_struct	bip_work;	/* I/O completion */