libredox: regenerate Cargo.toml from .orig (version 0.1.18, non-optional redox_syscall)

The generated Cargo.toml was stale (still 0.1.17 with
optional = true on redox_syscall) after the .orig bump.
Force-regenerate by manually editing both fields so the
generated file matches .orig. The previous build failure
(unresolved import redox_syscall) was due to this drift.

Discovered by running redbear-mini build after the
nice-mapping, affinity-mask, deadlock, and proc-path
fixes landed.

Cargo.toml

@@ -12,7 +12,7 @@
 [package]
 edition = "2021"
 name = "libredox"
-version = "0.1.17"
+version = "0.1.18"
 authors = ["4lDO2 <4lDO2@protonmail.com>"]
 build = false
 exclude = ["target"]
@@ -72,4 +72,3 @@ optional = true
 [dependencies.redox_syscall]
 path = "../syscall"
 version = "0.8"
-optional = true