hvc_console: use "*_console" nomenclature to avoid modpost warning.

The use of "hvc_con_driver" as the name for a file-static "struct
console" with a ".setup" field pointing to an __init function causes
a modpost warning, since a non-initdata structure points to init code.
Using "hvc_console" as the name triggers the hacky "*_console"
workaround in modpost to silence the warning, and is the same thing
that most of the other console drivers already do.

I made the same change in hvsi.c since I happened to notice it was
likely to suffer from the same problem.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>