fix: libc: use long for 64-bit types on aarch64

Use long instead of long long on aarch64 for 64_t stdint types.
Introduce inttypes.h to properly support printf format specifiers for
fixed width types for such change.

Change-Id: I0bca594687a996fde0a9702d7a383055b99f10a1
Signed-off-by: Scott Branden <scott.branden@broadcom.com>
diff --git a/services/std_svc/spmd/spmd_pm.c b/services/std_svc/spmd/spmd_pm.c
index ac962ea..6ebafca 100644
--- a/services/std_svc/spmd/spmd_pm.c
+++ b/services/std_svc/spmd/spmd_pm.c
@@ -6,6 +6,9 @@
 
 #include <assert.h>
 #include <errno.h>
+#include <inttypes.h>
+#include <stdint.h>
+
 #include <lib/el3_runtime/context_mgmt.h>
 #include <lib/spinlock.h>
 #include "spmd_private.h"
@@ -110,7 +113,7 @@
 
 	rc = spmd_spm_core_sync_entry(ctx);
 	if (rc != 0ULL) {
-		ERROR("%s failed (%llu) on CPU%u\n", __func__, rc,
+		ERROR("%s failed (%" PRIu64 ") on CPU%u\n", __func__, rc,
 			linear_id);
 		ctx->state = SPMC_STATE_OFF;
 		return;
@@ -138,7 +141,7 @@
 
 	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 (%" PRIu64 ") on CPU%u\n", __func__, rc, linear_id);
 	}
 
 	/* Expect a direct message response from the SPMC. */