kernel/heap: Increase the guarded heap 'initial' & 'grow' sizes.

With the standard defaults it wastes too much memory and didn't boot.
With these it successfully boots to desktop, for me at least.

headers/private/kernel/heap.h

@@ -20,7 +20,12 @@
 // ... and a lot of reserves to keep running.
 #define HEAP_GROW_SIZE				128 * 1024 * 1024
 
-#else // USE_GUARDED_HEAP_FOR_MALLOC && USE_GUARDED_HEAP_FOR_OBJECT_CACHE
+#elif USE_GUARDED_HEAP_FOR_MALLOC
+
+#define INITIAL_HEAP_SIZE			32 * 1024 * 1024
+#define HEAP_GROW_SIZE				32 * 1024 * 1024
+
+#else
 
 // allocate 16MB initial heap for the kernel
 #define INITIAL_HEAP_SIZE			16 * 1024 * 1024
@@ -31,7 +36,7 @@
 // use areas for allocations bigger than 1MB
 #define HEAP_AREA_USE_THRESHOLD		1 * 1024 * 1024
 
-#endif // !(USE_GUARDED_HEAP_FOR_MALLOC && USE_GUARDED_HEAP_FOR_OBJECT_CACHE)
+#endif
 
 
 // allocation/deallocation flags for {malloc,free}_etc()