[NTOS] Fix boot on UP build - PrcbLocks are not used on UP (#6391)

On the uniprocessor kernel KiAcquirePrcbLock is a stub that doesn't modify the current Prcb's PrcbLock value.
Quickly protect this assert around CONFIG_SMP

ntoskrnl/include/internal/ke_x.h

@@ -1359,7 +1359,9 @@ KxQueueReadyThread(IN PKTHREAD Thread,
 
     /* Sanity checks */
     ASSERT(Prcb == KeGetCurrentPrcb());
+#ifdef CONFIG_SMP
     ASSERT(Prcb->PrcbLock != 0);
+#endif
     ASSERT(Thread->State == Running);
     ASSERT(Thread->NextProcessor == Prcb->Number);