[NTOSKRNL] Implement the support for reserve IRP in IO

[NTOSKRNL] Implement the support for reserve IRP in IO

The reserve IRP is an IRP which is allocated on system boot and kept during
the whole system life. Its purpose is to allow page reads in case of
low-memory situations where the system doesn't have enough memory left
to allocate an IRP to read from the page file (would be catastrophic situation).