epson2: Add the Epson XP-427 as supported

See https://alioth.debian.org/tracker/index.php?func=detail&aid=315805&group_id=30186&atid=410366

backend/epson2_usb.c

@@ -171,6 +171,7 @@ SANE_Word sanei_epson_usb_product_ids[] = {
   0x8ca, /* L850 Series */
   0x8cd, /* WF-R4640 Series, WF-R5690 Series */
   0x8d0, /* PX-M350F, WF-M5690 Series */
+  0x1116, /* XP-427 */
   0				/* last entry - this is used for devices that are specified
 				   in the config file as "usb <vendor> <product>" */
 };

doc/descriptions/epson2.desc

@@ -3382,6 +3382,12 @@
 :status     :complete
 :comment    "network interface supported via DFSG non-free iscan-network-nt package<br>all-in-one"
 
+:model      "XP-427"
+:interface  "USB"
+:usbid      "0x04b8" "0x1116"
+:status     :good
+:comment    "network interface supported via DFSG non-free iscan-network-nt package<br>all-in-one"
+
 :model      "XP-600 Series"
 :interface  "USB"
 :usbid      "0x04b8" "0x089e"