os.linux: faccessat wrapper prefer to faccessat syscall when flags is zero.
This make `fs.Dir.access` has compatibility like the zig version before.
With this change the `zig build --search-prefix` command would work again like
the zig 0.14 version when used on Ubuntu22.04, kernel version 5.4.
a7769e25beQun He committed on 8/25/2025, 6:27:59 PM· committed by Andrew Kelleyparent5a0cf21