In msSHPReadShape also recognize nParts == 0 as a corrupted feature, thu...

...s logging "Corrupted feature encountered." with the hEntity, nPoints, and nParts of the feature rather than falling through and having the (psSHP->panParts == NULL) check trigger an "Out of memory" error; psSHP->panParts is NULL because zero bytes were requested due to nParts being zero, not because of a genuine memory allocation failure.