forked from Mirrors/opensbi

sbi_ipi_init() expects the platform warm init function to clear IPIs on the local hart, but there is already a generic function to do this. After this change, none of the existing drivers need a warm init callback. Signed-off-by: Samuel Holland <samuel.holland@sifive.com> Reviewed-by: Anup Patel <anup@brainfault.org>