By default, the opkg-key command is not included in pokg package because
it is only installed when gpg support is enabled. We'd better check if
it exists before run 'opkg-key populate' in pkg_postinst.
(From OE-Core rev: 096a03659cdfa99ca2b4b50ff37d6f2001d0bc90)
Signed-off-by: Yi Zhao <yi.zhao@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
d15a8d87b6