Kernel: Fix awkward RTC log message at boot

Kernel/RTC.cpp

@@ -155,7 +155,7 @@ time_t now()
     unsigned year, month, day, hour, minute, second;
     read_registers(year, month, day, hour, minute, second);
 
-    klog() << "year: " << year << ", month: " << month << ", day: " << day;
+    klog() << "RTC: Year: " << year << ", month: " << month << ", day: " << day;
 
     ASSERT(year >= 2018);