HID: intel-thc-hid: Intel-quickspi: Fix some error codes

HID: intel-thc-hid: Intel-quickspi: Fix some error codes

If we have a partial read that is supposed to be treated as failure but
in this code we forgot to set the error code.  Return -EINVAL.

Fixes: 9d8d51735a3a ("HID: intel-thc-hid: intel-quickspi: Add HIDSPI protocol implementation")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Even Xu <even.xu@intel.com>
Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Jiri Kosina <jkosina@suse.com>