firmware: stratix10-svc: fix kernel-doc markups

There are some common comments marked, instead, with kernel-doc
notation, which won't work.

While here, rename an identifier, in order to match the
function prototype below kernel-doc markup.

Acked-by: Richard Gong <richard.gong@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/02a1eb47767e01e875d8840805b8b2d4f3c6bdee.1610610937.git.mchehab+huawei@kernel.org


Signed-off-by: Jonathan Corbet <corbet@lwn.net>