The sama7 sub target does not have USB support, the feature should not
be activated there. OpenWrt can automatically detect if the target
supports USB by using the scripts/target-metadata.pl script. With the
automatic detection USB support will only get activated on subtargest
which actually support USB like sam9x and sama5.
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit f6d566301ee3dc12fd41e131f89dfc4777b002f3)
d0965dc174