Clean up property setting code.

In particular, ensure that all property_set failures are reported.

Change-Id: Iab94a28bcba2346868c0f39bcfe26e55a2c55562
diff --git a/init/init.cpp b/init/init.cpp
index dda2aeb..1449bc6 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -807,9 +807,7 @@
         std::replace(dt_file.begin(), dt_file.end(), ',', '.');
 
         std::string property_name = android::base::StringPrintf("ro.boot.%s", dp->d_name);
-        if (property_set(property_name.c_str(), dt_file.c_str())) {
-            ERROR("Could not set property %s to value %s", property_name.c_str(), dt_file.c_str());
-        }
+        property_set(property_name.c_str(), dt_file.c_str());
     }
 }