scsi: docs: megaraid: Clarify chapter heading

scsi: docs: megaraid: Clarify chapter heading

Include "Megaraid" in the chapter heading so that it is clear
what subject the document is about. This improves viewing in the TOC.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20230518212749.18266-10-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: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Sumit Saxena <sumit.saxena@broadcom.com>
Cc: Shivasharan S <shivasharan.srikanteshwara@broadcom.com>
Cc: megaraidlinux.pdl@broadcom.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>