Move read sync code into sync submodule

examples/stdin_info.rs

@@ -10,7 +10,7 @@ fn real_main() -> i32 {
     let mut buf = [0u8; 16];
 
     loop {
-        match zip::read::read_zipfile_from_stream(&mut stdin_handle) {
+        match zip::read::sync::read_zipfile_from_stream(&mut stdin_handle) {
             Ok(Some(mut file)) => {
                 println!(
                     "{}: {} bytes ({} bytes packed)",

fuzz/fuzz_targets/fuzz_read.rs

@@ -1,7 +1,7 @@
 #![no_main]
 use libfuzzer_sys::fuzz_target;
 use std::io::{Read, Seek, SeekFrom};
-use zip::read::read_zipfile_from_stream;
+use zip::read::sync::read_zipfile_from_stream;
 
 const MAX_BYTES_TO_READ: u64 = 1 << 24;