lsi: add 53C810 variant

Currently, treat it exactly as a 53C895A.
53C895A is a 53C810 with more capabilities, so this should work.

However, this lets us test different code paths on Linux, which
don't use lastest features if it detect a 810, or on some OSes
which only support 810 and not 895A (like very old Windows NT
versions).

Signed-off-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>