[OPENMP] Add the test to check that the libomptarget does not cause

infinite loop on removing non-mapped pointer-with-object.

Added test to check that libomptarget does not cause infinite loop when
trying to unmap the pointer-with-object data that was not previously
mapped.

git-svn-id: https://llvm.org/svn/llvm-project/openmp/trunk@343344 91177308-0d34-0410-b5e6-96231b3b80d8