Use %d for int32_t

Discovered by the upcoming compiler update.

Test: build
Change-Id: I0314ae298bc84fb07fda8736a827642c849afdc9
diff --git a/services/camera/libcameraservice/api2/CameraDeviceClient.cpp b/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
index c03e8a2..09c2d82 100644
--- a/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
+++ b/services/camera/libcameraservice/api2/CameraDeviceClient.cpp
@@ -668,7 +668,7 @@
 
     if (mInputStream.configured) {
         String8 msg = String8::format("Camera %s: Already has an input stream "
-                "configured (ID %zd)", mCameraIdStr.string(), mInputStream.id);
+                "configured (ID %d)", mCameraIdStr.string(), mInputStream.id);
         ALOGE("%s: %s", __FUNCTION__, msg.string() );
         return STATUS_ERROR(CameraService::ERROR_ALREADY_EXISTS, msg.string());
     }