Fix 4 E0277 errors in daemon/src/lib.rs where scheme_root()
and create_this_scheme_fd() return syscall::error::Error but
the function returns syscall::Error. Add .map_err() conversions.
redox-driver-sys errors (6 remaining E0308/E0061 in dma.rs/io.rs)
are pre-existing API mismatches between libredox and redox_syscall
crate versions — not addressed here.
vasilito
ad85d9bf0c