libredox: remove redox_syscall from default features list

The default features list still had 'redox_syscall' as a
feature entry, but the redox_syscall dep is now non-optional
(made non-optional in commit 80d0eae so the acpi module
could unconditionally re-export AcPiVerb). Cargo rejects
this as a manifest error: 'feature default includes
redox_syscall, but redox_syscall is not an optional
dependency'.

The fix is to remove 'redox_syscall' from the default list.
Since the dep is non-optional now, the feature is redundant
anyway (always on by default). The .orig and the
auto-generated Cargo.toml are updated in sync.

The previous build failure (after Cargo.toml regen) was
uncovered by the next build attempt and fixed here.

Cargo.toml

@@ -33,7 +33,6 @@ default = [
     "base",
     "call",
     "std",
-    "redox_syscall",
     "protocol",
 ]
 mkns = ["ioslice"]

Cargo.toml.orig

@@ -21,7 +21,7 @@ exclude = ["target"]
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [features]
-default = ["base", "call", "std", "redox_syscall", "protocol"]
+default = ["base", "call", "std", "protocol"]
 base = ["libc"]
 call = ["base"]
 std = ["base"]