minor correction: WordPosInput doesn't force the bytes to be in littl…

…e endian order

chacha20/src/rng.rs

@@ -497,7 +497,7 @@ macro_rules! impl_chacha_rng {
             /// As with `get_word_pos`, we use a 36-bit number. Since the generator
             /// simply cycles at the end of its period (256 GiB), we ignore the upper 28
             /// bits of a `u64`. When given a `[u8; 5]`, we ignore the first 4 bits of the
-            /// last little endian byte.
+            /// last byte.
             #[inline]
             pub fn set_word_pos<W: Into<WordPosInput>>(&mut self, word_offset: W) {
                 let word_offset: WordPosInput = word_offset.into();