target: Fix WRITE_SAME usage with transport_get_size

For all flavours of WRITE_SAME, we only expect to handle a single block
of data-out buffer payload, regardless of the number of logical blocks
presented in the CDB.  This patch changes all flavours of WRITE_SAME in
transport_generic_cmd_sequencer() to pass '1' into transport_get_size()
instead of the extracted 'sectors' to properly handle the default usage
of sg_write_same without the --xferlen parameter.
Reported-by: Eric Seppanen <eric@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@risingtidesystems.com>

drivers/target/target_core_transport.c

@@ -3103,7 +3103,7 @@ static int transport_generic_cmd_sequencer(
 				goto out_unsupported_cdb;
 
 			if (sectors)
-				size = transport_get_size(sectors, cdb, cmd);
+				size = transport_get_size(1, cdb, cmd);
 			else {
 				pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not"
 				       " supported\n");
@@ -3365,7 +3365,7 @@ static int transport_generic_cmd_sequencer(
 			goto out_unsupported_cdb;
 
 		if (sectors)
-			size = transport_get_size(sectors, cdb, cmd);
+			size = transport_get_size(1, cdb, cmd);
 		else {
 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 			goto out_invalid_cdb_field;
@@ -3383,7 +3383,7 @@ static int transport_generic_cmd_sequencer(
 			goto out_unsupported_cdb;
 
 		if (sectors)
-			size = transport_get_size(sectors, cdb, cmd);
+			size = transport_get_size(1, cdb, cmd);
 		else {
 			pr_err("WSNZ=1, WRITE_SAME w/sectors=0 not supported\n");
 			goto out_invalid_cdb_field;