Enhance the base/rom extension to generate the symbol file of the rom built.
The symbol file is placed in epoc32/rom/<baseport_name>, along with the rom log and final oby file.
EXPORTS
GetAddressOfDataProxy__FRiRPvT1 @ 1 NONAME R3UNUSED ; GetAddressOfDataProxy(int &, void *&, void *&)
CheckWritableStaticData__Fv @ 2 NONAME ; CheckWritablStaticData(void)