[Clang][OpenMP] Fix run time crash when use_device_addr is used.

It is data mapping ordering problem.

According omp spec
If one or more map clauses are present, the list item conversions that
are performed for any use_device_ptr or use_device_addr clause occur
after all variables are mapped on entry to the region according to those
map clauses.

The change is to put mapping data for use_device_addr at end of data
mapping array.

Differential Revision: https://reviews.llvm.org/D134556