macho: do not write out ZEROFILL physically to file
Prior to this change, `__DATA,__bss` and `__DATA,__thread_bss` would
get actually, physically written out to the output file, unnecessarily
filling the output file with 0s.
252fb642d5Jakub Konka committed on 2/3/2022, 4:22:15 AM· committed by Andrew Kelleyparentdcbab17