Our check was extra cautious, we've audited crash_send_ipi
and it sends an IPI only to online CPU's. Removal of this
check should have not functional impact on crash kdump.
Signed-off-by: Balbir Singh <bsingharora@gmail.com> Reviewed-by: Nicholas Piggin <npiggin@gmail.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>