re PR go/92861 (Passes relative time to sem_timedwait on GNU/Hurd)

	PR go/92861
    runtime: don't define CLOCK_REALTIME in os_hurd.go
    
    It's already defined in sysinfo.go.
    
    Patch by Samuel Thibault.
    
    Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/210538

From-SVN: r279136

gcc/go/gofrontend/MERGE

-1da5ceb8daaab7a243fffd6a647554cf674716f8
+6f2bf15e15bf7516c393966577d72b79cba7f980
 
 The first line of this file holds the git revision number of the last
 merge done from the gofrontend repository.

libgo/go/runtime/os_hurd.go

@@ -125,7 +125,3 @@ func osinit() {
 		physPageSize = uintptr(getPageSize())
 	}
 }
-
-const (
-	_CLOCK_REALTIME = 0
-)