tests: virschema: Propagate errors from directory traversal in testSchemaDir
tests: virschema: Propagate errors from directory traversal in testSchemaDir

testSchemaDir is a helper which invokes the schema test using virTestRun
on all schema files. Since the function itself is not called inside
virTestRun any helper function call is not dispatched to the user and
thus it's hard to debug the test. Propagate errors from the directory
traversal.

Signed-off-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>
Reviewed-by: Michal Privoznik <83d82aaba2eed257f4814b0c239c260c4caaadf0@redhat.com>

olafhering/libvirt,nertpinx/libvirt,nertpinx/libvirt,libvirt/libvirt,nertpinx/libvirt,libvirt/libvirt,zippy2/libvirt,nertpinx/libvirt,libvirt/libvirt,crobinso/libvirt,crobinso/libvirt,jfehlig/libvirt,olafhering/libvirt,jardasgit/libvirt,zippy2/libvirt,zippy2/libvirt,fabianfreyer/libvirt,crobinso/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,zippy2/libvirt,jardasgit/libvirt,jfehlig/libvirt,jfehlig/libvirt,nertpinx/libvirt,crobinso/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,jardasgit/libvirt,libvirt/libvirt,fabianfreyer/libvirt,olafhering/libvirt,jardasgit/libvirt,olafhering/libvirt