fix(spmd): error macro to use correct print format

Following merge of [1] then [2] broke the build because of an incorrect
format specifier in an ERROR macro. Fix to use the correct print format.

[1] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/5437
[2] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/9211

Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
Change-Id: I14d4c31091f6a5f4c3252f6d810e9d2bb2f545c4
diff --git a/services/std_svc/spmd/spmd_main.c b/services/std_svc/spmd/spmd_main.c
index 1390d88..f5de549 100644
--- a/services/std_svc/spmd/spmd_main.c
+++ b/services/std_svc/spmd/spmd_main.c
@@ -212,7 +212,7 @@
 
 	rc = spmd_spm_core_sync_entry(ctx);
 	if (rc != 0ULL) {
-		ERROR("%s failed (%llu) on CPU%u\n", __func__, rc, linear_id);
+		ERROR("%s failed (%" PRId64 ") on CPU%u\n", __func__, rc, linear_id);
 	}
 
 	ctx->secure_interrupt_ongoing = false;