This is a partial fix for bug 34050.
This prevents callers of omp_set_lock (which does not hold __kmp_global_lock) from
ever seeing an uninitialized version of __kmp_i_lock_table.table.
It does not solve a use-after-free race condition if omp_set_lock obtains a pointer to
__kmp_i_lock_table.table before it is updated and then attempts to dereference
afterwards. That race is far less likely and can be handled in a separate patch.
The unit test usually segfaults on the current trunk revision. It passes with the patch.