We observe that the waiting time for DDR error injection is about 10 ms
and that for PCIe error injection is about 500 ms in Arm platfrom.

In this patch, we relax the response timeout to 1 second and allow user to
pass the time out value as a argument.

Spinning for 1ms was maybe ok. Spinning for up to 1s seems like a bad idea.

This code is executed inside a mutex ... so maybe it is safe to sleep instead of spin?

-Tony