runqemu: fix run from testimage with non-standard DEPLOY_DIR_IMAGE
testimage.bbclass uses runqemu to execute runtime tests on a qemu
target, this means that bitbake is already running and `bitbake -e`
can't be called to obtain bitbake variables.
runqemu tries to work around being unable to read values for
bitbake variables by inferring the MACHINE from the
DEPLOY_DIR_IMAGE setting, however if a user sets that variable in
a manner which doesn't follow the systems expectations (i.e. if
running `bitbake -c testimage` against a directory of pre-generated
images in a user-specified path) the inferring of the MACHINE name
from the DEPLOY_DIR_IMAGE location will fail.
It's possible that check_arg_machine() shouldn't cause runqemu to
fail and that runqemu should proceed with the user-supplied value
even if it can't be verified. This patch simply ensures that a
workflow where the user sets DEPLOY_DIR_IMAGE continues to work
without changing too much of the runqemu code.
[YOCTO #10238]
Signed-off-by: Joshua Lock <joshua.g.lock@intel.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
