Mikrotik RBM33G has got a USB-A port and mPCIe slots with USB 3.0 and USB
2.0 interfaces in use. The MediaTek MT7621 SoC has got an xHCI to provide
these interfaces. Therefore, enable kmod-usb3 to support them.
Fixes: 5684d087418d ("ramips: Add support for Mikrotik RouterBOARD RBM33g")
Signed-off-by: Chester A. Unal <chester.a.unal@arinc9.com>
(cherry picked from commit 61c9337d80318a49a5bcee586435b513fbdeacf7)
8b50f6c215