ExternalProject: Fix step dependency on mkdir step
When looking at list(FIND) result, zero index is ignored due to incorrect error handling, and users can't set dependencies on mkdir step.
Fixes: #20605 (closed)
Edited by Brad King
When looking at list(FIND) result, zero index is ignored due to incorrect error handling, and users can't set dependencies on mkdir step.
Fixes: #20605 (closed)