Remove has_redox_scheme

Redox OS is moving away from name:/path style paths to /scheme/name/path
style paths which are already handled correctly without has_redox_scheme.

library/std/src/path.rs

@@ -294,11 +294,6 @@ where
     }
 }
 
-// Detect scheme on Redox
-pub(crate) fn has_redox_scheme(s: &[u8]) -> bool {
-    cfg!(target_os = "redox") && s.contains(&b':')
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // Cross-platform, iterator-independent parsing
 ////////////////////////////////////////////////////////////////////////////////
@@ -2834,8 +2829,7 @@ impl Path {
         Components {
             path: self.as_u8_slice(),
             prefix,
-            has_physical_root: has_physical_root(self.as_u8_slice(), prefix)
+            has_physical_root: has_physical_root(self.as_u8_slice(), prefix),
-                || has_redox_scheme(self.as_u8_slice()),
             front: State::Prefix,
             back: State::Body,
         }

library/std/src/sys/path/unix.rs

@@ -62,10 +62,7 @@ pub(crate) fn absolute(path: &Path) -> io::Result<PathBuf> {
 }
 
 pub(crate) fn is_absolute(path: &Path) -> bool {
-    if cfg!(target_os = "redox") {
+    if cfg!(any(unix, target_os = "hermit", target_os = "wasi")) {
-        // FIXME: Allow Redox prefixes
-        path.has_root() || crate::path::has_redox_scheme(path.as_u8_slice())
-    } else if cfg!(any(unix, target_os = "hermit", target_os = "wasi")) {
         path.has_root()
     } else {
         path.has_root() && path.prefix().is_some()