asio: fix runtime dependencies for images with dev-pkgs in IMAGE_FEATURES

asio-dev created REDEPENS on asio which was not existent. This caused do_rootfs
for other packages fail with something like:

|  * satisfy_dependencies_for: Cannot satisfy the following dependencies for abiword-dev:
|  * 	asio (= 1.4.1-r0.0) *
|  * opkg_install_cmd: Cannot install package abiword-dev.

Signed-off-by: Andreas Müller <schnitzeltony@googlemail.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>