[OpenMP][IRBuilder] Fix createSections

Fix for the case when there are no instructions in the entry basic block before the call
to `createSections`

Reviewed By: Meinersbur

Differential Revision: https://reviews.llvm.org/D114143

GitOrigin-RevId: ec97e1206abd6f30a1b549db62e87bea8dee0082
1 file changed