scsi: docs: dc395x: Shorten the chapter heading

Make the heading be concise yet still descriptive.
This makes the subsystem table of contents more readable (IMO).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230518212749.18266-6-rdunlap@infradead.org
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Oliver Neukum <oliver@neukum.org>
Cc: Ali Akcaagac <aliakc@web.de>
Cc: Jamie Lenehan <lenehan@twibble.org>
Cc: dc395x@twibble.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Documentation/scsi/dc395x.rst

 .. SPDX-License-Identifier: GPL-2.0
 
-======================================
-README file for the dc395x SCSI driver
-======================================
+==================
+dc395x SCSI driver
+==================
 
 Status
 ------