msdosfs and cd9660: stat(2) returns garbled birthtime

Hi,

at least msdosfs and cd9660 do not fill the birthtime for the stat(2)
syscall. Thus stat(1) will return different values per call:

root_at_fs2:/export# stat -f "%Da %Dm %Dc %DB" /export/msdosfs
/export/cd9660 /export/ufs
315532800 315532800 315532800 -926228096
1164792535 1163757053 1163757053 -926228096
1167168567 1166109700 1166131188 1162567651
root_at_fs2:/export# stat -f "%Da %Dm %Dc %DB" /export/msdosfs
/export/cd9660 /export/ufs
315532800 315532800 315532800 -926230272
1164792535 1163757053 1163757053 -926230272
1167168567 1166109700 1166131188 1162567651
root_at_fs2:/export# stat -f "%Da %Dm %Dc %DB" /export/msdosfs
/export/cd9660 /export/ufs
315532800 315532800 315532800 -929051264
1164792535 1163757053 1163757053 -929051264
1167168567 1166109700 1166131188 1162567651

The code in cd9660_getattr() and msdosfs_getattr() should be
augmented. But what value to put into the field? Clearly, a constant
would be preferred instead of an uninitialized value.

Uli