runqemu: work with tap device names that end with a colon
On Fedora systems (and likely others), ifconfig returns interface
names that end with a colon. Make sure we strip the colon off the
tap device name before using it.
This fixes [YOCTO #3028]
Signed-off-by: Scott Garman <scott.a.garman@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>