include stdint.h for int32_t/uint32_t

Signed-off-by: Jussi Kukkonen <jussi.kukkonen@intel.com>
Reviewed-by: Yong Bakos <ybakos@humanoriented.com>
diff --git a/clients/scaler.c b/clients/scaler.c
index f504c73..17ca55d 100644
--- a/clients/scaler.c
+++ b/clients/scaler.c
@@ -24,6 +24,7 @@
 
 #include "config.h"
 
+#include <stdint.h>
 #include <stdio.h>
 #include <string.h>
 #include <assert.h>