Validate 'glance image-create' exit code

qa_crobarsetup.sh checks if SP3-64 image is available in glance, if it
isn't, then it's uploaded to glance, if glance image-create fails then
exit with error.

It makes sense to exit with error, because the next steps in the script involve the usage of SP3-64 image.
glance image-list produces a different format, so the glance.out file could not be parsed in L1123
glance image-show SP3-64 would be an option... but I dont really see the point of the else part, because the glance.out file would still be around from the previous upload, thus allowing to run mkcloud testsetup multiple times.