x86/ibt: Handle FineIBT in handle_cfi_failure()

Sami reminded me that FineIBT failure does not hook into the regular
CFI failure case, and as such CFI_PERMISSIVE does not work.

Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lkml.kernel.org/r/20250214092619.GB21726@noisy.programming.kicks-ass.net