ar71xx: remove Arduino Yun 8 MiB prototype

The Arduino Yun has 16 MiB flash. Early prototype boards with 8 MiB were
not available for sell:

https://blog.arduino.cc/2013/08/21/updating-about-arduino-yun-and-arduino-robot/

Signed-off-by: Camille Bilodeau <camille.bilodeau@protonmail.com>

target/linux/ar71xx/image/legacy-devices.mk

@@ -167,12 +167,6 @@ define LegacyDevice/WLR8100
 endef
 LEGACY_DEVICES += WLR8100
 
-define LegacyDevice/YUN_8M
-  DEVICE_TITLE := Arduino Yun based on Atheros AR9331 (8MB flash)
-  DEVICE_PACKAGES := kmod-usb-core kmod-usb2
-endef
-LEGACY_DEVICES += YUN_8M
-
 define LegacyDevice/YUN_16M
   DEVICE_TITLE := Arduino Yun based on Atheros AR9331 (16MB flash)
   DEVICE_PACKAGES := kmod-usb-core kmod-usb2

target/linux/ar71xx/image/legacy.mk

@@ -277,7 +277,6 @@ wndr4300_mtdlayout=mtdparts=ar934x-nfc:256k(u-boot)ro,256k(u-boot-env)ro,256k(ca
 zcn1523h_mtdlayout=mtdparts=spi0.0:256k(u-boot)ro,64k(u-boot-env)ro,6208k(rootfs),1472k(kernel),64k(configure)ro,64k(mfg)ro,64k(art)ro,7680k@0x50000(firmware)
 mynet_rext_mtdlayout=mtdparts=spi0.0:256k(u-boot)ro,7808k(firmware),64k(nvram)ro,64k(ART)ro
 zyx_nbg6716_mtdlayout=mtdparts=spi0.0:256k(u-boot)ro,64k(env)ro,64k(RFdata)ro,-(nbu);ar934x-nfc:2048k(zyxel_rfsd),2048k(romd),1024k(header),2048k(kernel),-(ubi)
-yun_mtdlayout_8M=mtdparts=spi0.0:256k(u-boot)ro,64k(u-boot-env)ro,6464k(rootfs),1280k(kernel),64k(nvram),64k(art)ro,7744k@0x50000(firmware)
 yun_mtdlayout_16M=mtdparts=spi0.0:256k(u-boot)ro,64k(u-boot-env)ro,14656k(rootfs),1280k(kernel),64k(nvram),64k(art)ro,15936k@0x50000(firmware)
 
 define Image/BuildKernel
@@ -905,7 +904,6 @@ $(eval $(call SingleProfile,AthLzma,64k,EWDORIN16M,ew-dorin-16M,EW-DORIN,ttyATH0
 $(eval $(call SingleProfile,AthLzma,64k,HORNETUBx2,hornet-ub-x2,HORNET-UB,ttyATH0,115200,$$(alfa_mtdlayout_16M),KRuImage,65536))
 $(eval $(call SingleProfile,AthLzma,64k,TUBE2H16M,tube2h-16M,TUBE2H,ttyATH0,115200,$$(alfa_mtdlayout_16M),KRuImage,65536))
 $(eval $(call SingleProfile,AthLzma,64k,WLR8100,wlr8100,WLR8100,ttyS0,115200,$$(wlr8100_mtdlayout),KRuImage))
-$(eval $(call SingleProfile,AthLzma,64k,YUN_8M,yun-8M,Yun,ttyATH0,250000,$$(yun_mtdlayout_8M),RKuImage))
 $(eval $(call SingleProfile,AthLzma,64k,YUN_16M,yun-16M,Yun,ttyATH0,250000,$$(yun_mtdlayout_16M),RKuImage))
 
 $(eval $(call SingleProfile,Belkin,64k,F9K1115V2,f9k1115v2,F9K1115V2,ttyS0,115200,$$(f9k1115v2_mtdlayout),BR-6679BAC))