fix check_no_isolation

Author: pvdrz

src/shims/time.rs

@@ -214,7 +214,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         let this = self.eval_context_mut();
 
         this.assert_target_os("windows", "QueryPerformanceCounter");
-        this.check_no_isolation("`QueryPerformanceCounter`")?;
 
         // QueryPerformanceCounter uses a hardware counter as its basis.
         // Miri will emulate a counter with a resolution of 1 nanosecond.
@@ -255,7 +254,6 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriEvalContextExt<'mir, 'tcx
         let this = self.eval_context_ref();
 
         this.assert_target_os("macos", "mach_absolute_time");
-        this.check_no_isolation("`mach_absolute_time`")?;
 
         // This returns a u64, with time units determined dynamically by `mach_timebase_info`.
         // We return plain nanoseconds.