scsi: docs: convert g_NCR5380.txt to ReST

Link: https://lore.kernel.org/r/a66e9ea704be6a7aa81b9864ad66a32b75ab808d.1583136624.git.mchehab+huawei@kernel.org


Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>