[llvm] [mlir] [OpenMP][MLIR][OMPIRBuilder] Add a small optional constant alloca raise function pass to finalize, utilised in convertTarget (PR #78818)

[via llvm-commits]

agozillon wrote:

Landed this PR now, if anyone encounters any unexpected behaviour relating to allocas being raised by this PR please drop a message here or send me a message and then we can revert the PR or make the necessary changes.

https://github.com/llvm/llvm-project/pull/78818