usb/u3g: Add support for QUECTEL EP06-E 4G modem

Add QUECTEL EP06-E modem support via USB for FreeBSD.
Tested and works like a ppp on FreeBSD-13.

Reviewed by: imp
PR: 269326
Approved by: re (cperciva)

(cherry picked from commit 0cec5b99b3c0484925f3cc0813040c160987bd45)
(cherry picked from commit 1256ad9b27b2eb34a066640e63039975ab4f8492)