[OpenMP] Add omp_get_device_num() and update several other device API functions
Add omp_get_device_num() function for 5.0 which returns the number of the device
the current thread is running on. Also, did some cleanup and updating of device
API functions to make them into weak functions that should be replaced with
libomptarget functions when libomptarget is present.
Patch by Terry Wilmarth
Differential Revision: https://reviews.llvm.org/D54342
git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@347799 91177308-0d34-0410-b5e6-96231b3b80d8
11 files changed
