Matt Harbison <matt_harbison@yahoo.com> [Fri, 04 Nov 2022 17:54:43 -0400] rev 49574
vfs: make the default opener mode binary
The default was already binary for `abstractvfs`, and the `vfs` implementation
adds binary mode if the caller didn't supply it. Therefore, it should be safe
for all vfs objects (and I don't think we want text reads anyway).