This patch implements teams affinity on the host.
The default is spread. A user can specify either spread, close, or
primary using KMP_TEAMS_PROC_BIND environment variable. Unlike
OMP_PROC_BIND, KMP_TEAMS_PROC_BIND is only a single value and is not a
list of values. The values follow the same semantics under the OpenMP
specification for parallel regions except T is the number of teams in
a league instead of the number of threads in a parallel region.
Differential Revision: https://reviews.llvm.org/D109921
Peyton, Jonathan L