The Windows sceKernelPread stopped going through pread when it learned to
return errors, and with it lost the random device read, so a pread on
/dev/urandom reached ReadFile on a handle that is not a disk and failed
with ESPIPE. Read random devices first, as the Linux path does.
A pread into a read-only guest mapping now returns EFAULT instead of
throwing, matching Linux and the AIO read beside it, so the Windows
guest memory test checks for that return.