Implement some more IoUring operations

Add timeout update, cancel_fd, epoll_wait, files_update, open, open_direct, f/madvice

don't implement f/madvice64 for now I doubt it is used by a lot of people in practice

Implement BufferGroup read_multishot

Try to make definition of function align as logically as posible with
liburing to make keeping our implementation in sync easy

TODO: add M/Fadvice enum flags
TODO: understand buffer_selection and how its different from BufferGroup

Signed-off-by: Bernard Assan <mega.alpha100@gmail.com>

Author: bernardassan

lib/std/os/linux.zig

@@ -8425,6 +8425,13 @@ pub const MADV = struct {
     pub const SOFT_OFFLINE = 101;
 };
 
+pub const Madvice = enum(u32) {
+    _, // TODO: add options
+};
+pub const Fadvice = enum(u32) {
+    _, // TODO: add options
+};
+
 pub const POSIX_FADV = switch (native_arch) {
     .s390x => if (@typeInfo(usize).int.bits == 64) struct {
         pub const NORMAL = 0;