Fix wait_until(infinity) for condition_variable

libcxx implements wait_until using wait_for, which in
its turn has to call a syscall that's basically wait_until,
causing a double conversion of the waiting time parameter.
Because of this, infinity detection code in those conversions
sometimes fail if the delat between the conversions is long
enough - causing a syscall error for 'invalid time'

This CL explicitly calls non-timed wait() instead.

Bug: 293223125
Bug: 292138960
Test: build + unit tests + presubmits
Change-Id: Id30fdfbe374b63fcaed627fcdf374f1e501a7807