We should have a spurious interrupt vector just incase we get one. The
handler doesn't need to do anything.
BUG=b:116777191
TEST=Booted depthcharge on grunt and inspected the register. I can't
generate a spurious interrupt, so I can't validate that the handler gets
called.
Change-Id: I9e49e617f4375eb5eb00d0715c1902f77e2bf284
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://review.coreboot.org/28880
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Martin Roth <martinroth@google.com>