libsoup-2.4: add intltool-native to DEPENDS

The configure script looks for this; most of the time dependency chains
ensure this is present but we need to be explicit or failures can
occur.

Reported by Nicolas Dechesne <nicolas.dechesne@linaro.org>

(From OE-Core master rev: 22e45ed7d74ceb4a719e7b5889400c20ed4a0783)

Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>