mvebu: remove ClearFog Pro SUPPORTED_DEVICES

A direct upgrade from previous swconfig version with
incompatible settings to DSA will break the internet.
Remove SUPPORTED_DEVICES so users cannot upgrade directly.

Signed-off-by: DENG Qingfang <dengqf6@mail2.sysu.edu.cn>
[rebase after Linksys rename, adjust title]
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

target/linux/mvebu/image/cortexa9.mk

@@ -221,7 +221,6 @@ define Device/solidrun_clearfog-pro-a1
   IMAGES := sdcard.img.gz
   IMAGE/sdcard.img.gz := boot-scr | boot-img-ext4 | sdcard-img-ext4 | gzip | append-metadata
   DEVICE_DTS := armada-388-clearfog-pro armada-388-clearfog-base
-  SUPPORTED_DEVICES += armada-388-clearfog armada-388-clearfog-pro
   UBOOT := clearfog-u-boot-spl.kwb
   BOOT_SCRIPT := clearfog
 endef