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
_ll_sto_d @ 1 NONAME ; _ll_sto_d
_ll_usto_d @ 2 NONAME ; _ll_usto_d
_ll_sfrom_d @ 3 NONAME ; _ll_sfrom_d
_ll_usfrom_d @ 4 NONAME ; _ll_usfrom_d
_ll_sfrom_f @ 5 NONAME ; _ll_sfrom_f
_ll_sto_f @ 6 NONAME ; _ll_sto_f
_ll_usfrom_f @ 7 NONAME ; _ll_usfrom_f
_ll_usto_f @ 8 NONAME ; _ll_usto_f