klteusc: set carrier operator alpha and numeric values for US Cellular.

* This is the correct way to do it, and fixed some bugs on the jflte when
it was added so might as well follow

Change-Id: Ie097656199a9fd9c47f2d74768fc1e84fc01cd5a
klteusc: add "klte" to build barrier to fix flashing issues.

* Some recoveries report the device as klte regardless of the variant,
because of this the ROM fails to flash. This will at least allow
flashing without editing the updater-script manually.

Change-Id: Ifbc920e50e8eb3ba1c33c4aca843436e449f2645