usb: gadget: f_uac1: endianness fixes.

As per USB spec, multiple-bytes fields are stored
in little-endian order. Use CPU<->LE helpers for
such fields.

Change-Id: Iba552e473a39be4adafd641692d5aca12f7adf06
Signed-off-by: Ruslan Bilovol <ruslan.bilovol@gmail.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Git-commit: 42370b821168e6730ec4c7d988aeadc1260c7b4d
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>