Families up to and including 0x16 allow access to the injection
hardware. Starting with family 0x17, access to those registers is
blocked by security policy.

Limit that only on the families which support it.
Suggested-by: NYazen Ghannam <yazen.ghannam@amd.com>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20201222180013.GD13463@zn.tnic