Fix broken SpinLock.

The SpinLock was all backwards and didn't actually work. Fixing it exposed
how wrong most of the locking here is.

I need to come up with a better granularity here.

Kernel/kmalloc.cpp

@@ -20,7 +20,7 @@ typedef struct
 } PACKED allocation_t;
 
 #define CHUNK_SIZE  128
-#define POOL_SIZE   (512 * 1024)
+#define POOL_SIZE   (1024 * 1024)
 
 #define BASE_PHYS   0x200000