Traceflags: Add SCons function to created a traceflag instead of having one file with them all.

--HG--
extra : convert_revision : 427f6bd8f050861ace3bc0d354a1afa5fc8319e6

src/mem/SConscript

@@ -49,3 +49,10 @@ if env['FULL_SYSTEM']:
 else:
     Source('page_table.cc')
     Source('translating_port.cc')
+
+TraceFlag('Bus')
+TraceFlag('BusAddrRanges')
+TraceFlag('BusBridge')
+TraceFlag('LLSC')
+TraceFlag('MMU')
+TraceFlag('MemoryAccess')