lib: sbi_ipi: Move initial IPI clear to sbi_ipi_init()

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>

lib/utils/ipi/aclint_mswi.c

@@ -66,14 +66,6 @@ static struct sbi_ipi_device aclint_mswi = {
 	.ipi_clear = mswi_ipi_clear
 };
 
-int aclint_mswi_warm_init(void)
-{
-	/* Clear IPI for current HART */
-	mswi_ipi_clear();
-
-	return 0;
-}
-
 int aclint_mswi_cold_init(struct aclint_mswi_data *mswi)
 {
 	u32 i;