Fix format string mismatch. Clang build fix.

The gralloc usage flags are an enum, which is backed by an
implementation defined type. Both gcc and clang are making this a long
long. All the values are hard coded to fit within 8 hex characters
though, so just make the cast.

Change-Id: I4a9778a24c2cbf7fb663371d208e30c4921e170d
diff --git a/media/jni/android_media_ImageWriter.cpp b/media/jni/android_media_ImageWriter.cpp
index 294cd84..634ba64 100644
--- a/media/jni/android_media_ImageWriter.cpp
+++ b/media/jni/android_media_ImageWriter.cpp
@@ -293,7 +293,8 @@
         res = native_window_set_usage(anw.get(), GRALLOC_USAGE_SW_WRITE_OFTEN);
         if (res != OK) {
             ALOGE("%s: Configure usage %08x for format %08x failed: %s (%d)",
-                    __FUNCTION__, GRALLOC_USAGE_SW_WRITE_OFTEN, format, strerror(-res), res);
+                  __FUNCTION__, static_cast<unsigned int>(GRALLOC_USAGE_SW_WRITE_OFTEN),
+                  format, strerror(-res), res);
             jniThrowRuntimeException(env, "Failed to SW_WRITE_OFTEN configure usage");
             return 0;
         }