Fix 64-bit build issues

Fix some type comparisons/mismatches:

- msg->what() is uint32_t (32-bit), not size_t (64-bit)
- std::max() for long long (128-bit) vs int64_t (64-bit)

Bug: 158659480
Change-Id: Ic00e6097c3ec8286e9759d286017b5e936779368
diff --git a/drm/drmserver/DrmManager.cpp b/drm/drmserver/DrmManager.cpp
index 9a32cc5..74e3223 100644
--- a/drm/drmserver/DrmManager.cpp
+++ b/drm/drmserver/DrmManager.cpp
@@ -99,13 +99,13 @@
         }
         default:
         {
-            ALOGW("Unrecognized message type: %zd", msg->what());
+            ALOGW("Unrecognized message type: %u", msg->what());
         }
     }
 }
 
 int64_t DrmManager::getMetricsFlushPeriodUs() {
-    return 1000 * 1000 * std::max(1ll, property_get_int64("drmmanager.metrics.period", 86400));
+    return 1000 * 1000 * std::max(1ll, (long long)property_get_int64("drmmanager.metrics.period", 86400));
 }
 
 void DrmManager::recordEngineMetrics(