usbdevs: add new Microchip USB-Ethernet device IDs

LAN7800 USB 3.1 to 10/100/1000 Ethernet with PHY
LAN7801 USB 3.1 to 10/100/1000 Ethernet with RGMII interface

Also update manufacturer name for the Vendor ID. Microchip acquired
SMSC in May 2012.

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