HID: intel-ish-hid: ipc: remove unused macro

The macro timed_wait_for() in utils.h isn't used in current ipc
driver, so remove it for avoiding confusion.

Signed-off-by: Even Xu <even.xu@intel.com>
Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>