Merge pull request #13755 from AGlass0fMilk/fix-init-os-timer

Fix MBED_ERROR call in init_os_timer

platform/source/mbed_os_timer.cpp

@@ -52,7 +52,11 @@ OsTimer *init_os_timer()
 #elif DEVICE_USTICKER
         os_timer = new (os_timer_data) OsTimer(get_us_ticker_data());
 #else
-        MBED_ERROR("OS timer not available");
+        MBED_ERROR(
+            MBED_MAKE_ERROR(
+                MBED_MODULE_PLATFORM,
+                MBED_ERROR_CODE_CONFIG_UNSUPPORTED),
+            "OS timer not available");
 #endif
     }