ramips: drop support for ALLNET ALL0239-3G and Sitecom WL-341 v3

Beside one exception, no one took care of these two remaining boards
still using the legacy image build code during the last two years.

Since OpenWrt 14.07 the ALLNET ALL0239-3G image building is broken.

The Sitecom WL-341 v3 image build code looks pretty hackish and broken.
It's questionable if the legacy image works as all.

Signed-off-by: Mathias Kresin <dev@kresin.me>

target/linux/ramips/base-files/lib/ramips.sh

@@ -34,9 +34,6 @@ ramips_board_detect() {
 	*"Air3GII")
 		name="air3gii"
 		;;
-	*"ALL0239-3G")
-		name="all0239-3g"
-		;;
 	*"ALL0256N (4M)")
 		name="all0256n-4M"
 		;;
@@ -586,9 +583,6 @@ ramips_board_detect() {
 	*"WL-330N3G")
 		name="wl-330n3g"
 		;;
-	*"WL-341 v3")
-		name="wl-341v3"
-		;;
 	*"WL-351 v1 002")
 		name="wl-351"
 		;;