Fix crash on negative stat f_type (Rust-port regression)

Fixes #11219

src/path.rs

@@ -707,7 +707,12 @@ fn path_remoteness(path: &wstr) -> DirRemoteness {
         // these are in varying headers. Simply hard code them.
         // Note that we treat FUSE filesystems as remote, which means we lock less on such filesystems.
         // NOTE: The cast is necessary for 32-bit systems because of the 4-byte CIFS_MAGIC_NUMBER
-        match usize::try_from(buf.f_type).unwrap() {
+        const _: () = assert!({
+            use std::mem;
+            let f_type = unsafe { mem::zeroed::<libc::statfs>() }.f_type;
+            mem::size_of_val(&f_type) <= mem::size_of::<usize>()
+        });
+        match buf.f_type as usize  {
             0x5346414F | // AFS_SUPER_MAGIC - Andrew File System
             0x6B414653 | // AFS_FS_MAGIC - Kernel AFS and AuriStorFS
             0x73757245 | // CODA_SUPER_MAGIC - Coda File System