HID: hyperv: Correctly access fields declared as __le16

HID: hyperv: Correctly access fields declared as __le16

Add the use of le16_to_cpu() for fields declared as __le16. Because
Hyper-V only runs in Little Endian mode, there's no actual bug.
The change is made in the interest of general correctness in
addition to making sparse happy. No functional change.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Link: https://lore.kernel.org/r/1654660177-115463-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Wei Liu <wei.liu@kernel.org>