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
CreateLogicalDevice__Fv @ 1 NONAME R3UNUSED ; CreateLogicalDevice(void)
LinkedTest9__Fv @ 2 NONAME R3UNUSED ; LinkedTest9(void)
LinkedTest1__Fv @ 3 NONAME R3UNUSED ; LinkedTest1(void)
LinkedTest2__Fv @ 4 NONAME R3UNUSED ; LinkedTest2(void)
LinkedTest3__Fv @ 5 NONAME R3UNUSED ; LinkedTest3(void)
LinkedTest4__Fv @ 6 NONAME R3UNUSED ; LinkedTest4(void)
LinkedTest5__Fv @ 7 NONAME R3UNUSED ; LinkedTest5(void)
LinkedTest6__Fi @ 8 NONAME R3UNUSED ; LinkedTest6(int)
LinkedTest7__Fv @ 9 NONAME R3UNUSED ; LinkedTest7(void)
LinkedTest8__FUl @ 10 NONAME R3UNUSED ; LinkedTest8(unsigned long)