lib/oeqa/runtime/multilib.py: use readelf instead of file

lib/oeqa/runtime/multilib.py: use readelf instead of file

file was pulled by rpm in sato images, readelf comes with binutils
so it's in ipk/deb too.
Also the test was looking at connmand instead of connman-applet
(which is what the testcase says and the AB nightly-multilib target installs)

(From OE-Core rev: c2c47a002996b8dbcf9b311dff677202b1f11a64)

Signed-off-by: Stefan Stanacar <stefanx.stanacar@intel.com>
Signed-off-by: Saul Wold <sgw@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>