scsi: target: add driver-api document

Add a driver-api document for target/iSCSI interfaces.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
To: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
Cc: linux-scsi@vger.kernel.org
Cc: target-devel@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst
index 6d8352c..f7aca56 100644
--- a/Documentation/driver-api/index.rst
+++ b/Documentation/driver-api/index.rst
@@ -34,6 +34,7 @@
    edac
    scsi
    libata
+   target
    mtdnand
    miscellaneous
    w1