[SCSI] bsg: separate bsg and SCSI (so SCSI can be modular)

This patch moves the bsg registration into SCSI so that bsg no longer
has a dependency on the scsi_interface_register API.

This can be viewed as a temporary expedient until we can get universal
bsg binding sorted out properly.  Also use the sdev bus_id as the
generic bsg name (to avoid clashes with the queue name).

Acked-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Acked-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
diff --git a/block/Kconfig b/block/Kconfig
index 0768741..ca2ef4e 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -53,7 +53,7 @@
 
 config BLK_DEV_BSG
 	bool "Block layer SG support v4 (EXPERIMENTAL)"
-	depends on (SCSI=y) && EXPERIMENTAL
+	depends on EXPERIMENTAL
 	---help---
 	Saying Y here will enable generic SG (SCSI generic) v4 support
 	for any block device.