lib: sbi: skip wait_for_coldboot when coolboot done

When warmboot via HSM, coolboot has been completed and
wait_for_coldboot can be skipped to speed up.

Signed-off-by: Xiang W <wxjstz@126.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
diff --git a/lib/sbi/sbi_init.c b/lib/sbi/sbi_init.c
index 005985d..6a98e13 100644
--- a/lib/sbi/sbi_init.c
+++ b/lib/sbi/sbi_init.c
@@ -195,6 +195,9 @@
 {
 	unsigned long saved_mie, cmip;
 
+	if (__smp_load_acquire(&coldboot_done))
+		return;
+
 	/* Save MIE CSR */
 	saved_mie = csr_read(CSR_MIE);