Kernel: Verify interrupts are disabled when interacting with Mutexes

This should help prevent deadlocks where a thread blocks on a Mutex
while interrupts are disabled, and makes it impossible for the holder of
the Mutex to make forward progress because it cannot be scheduled in.

Hide it behind a new debug macro LOCK_IN_CRITICAL_DEBUG for now, because
Ext2FS takes a series of Mutexes from the page fault handler, which
executes with interrupts disabled.

Kernel/Debug.h.in

@@ -166,6 +166,10 @@
 #cmakedefine01 LOCK_DEBUG
 #endif
 
+#ifndef LOCK_IN_CRITICAL_DEBUG
+#cmakedefine01 LOCK_IN_CRITICAL_DEBUG
+#endif
+
 #ifndef LOCK_RESTORE_DEBUG
 #cmakedefine01 LOCK_RESTORE_DEBUG
 #endif