optimize Eq implementation for paths

Filesystems generally have a tree-ish structure which means
paths are more likely to share a prefix than a suffix. Absolute paths
are especially prone to share long prefixes.

Author: the8472

library/std/src/path.rs

@@ -951,7 +951,7 @@ impl FusedIterator for Components<'_> {}
 impl<'a> cmp::PartialEq for Components<'a> {
     #[inline]
     fn eq(&self, other: &Components<'a>) -> bool {
-        Iterator::eq(self.clone(), other.clone())
+        Iterator::eq(self.clone().rev(), other.clone().rev())
     }
 }