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
_Z19CreateLogicalDevicev @ 1 NONAME
_Z11LinkedTest1v @ 2 NONAME
_Z11LinkedTest2v @ 3 NONAME
_Z11LinkedTest3v @ 4 NONAME
_Z11LinkedTest4v @ 5 NONAME
_Z11LinkedTest5v @ 6 NONAME
_Z11LinkedTest6i @ 7 NONAME
_Z11LinkedTest7v @ 8 NONAME
_Z11LinkedTest8m @ 9 NONAME
_Z11LinkedTest9v @ 10 NONAME