Kernel: kmalloc has now somewhat dynamic storage

Allocations bigger than PAGE_SIZE and those not forced to be identity
mapped are now done on a GeneralAllocator. This allows us to use kmalloc
for big allocations; bigger than the fixed 1 MiB storage.

This is still a hack and the whole kmalloc will have to be rewritten at
some point, but for now this does the job :D

kernel/include/kernel/Memory/kmalloc.h

@@ -1,10 +1,15 @@
 #pragma once
 
+#include <BAN/Optional.h>
+#include <kernel/Memory/Types.h>
+
 #include <stddef.h>
 
 void kmalloc_initialize();
 void kmalloc_dump_info();
 
-void* kmalloc(size_t);
-void* kmalloc(size_t, size_t);
+void* kmalloc(size_t size);
+void* kmalloc(size_t size, size_t align, bool force_identity_map = false);
 void kfree(void*);
+
+BAN::Optional<Kernel::paddr_t> kmalloc_paddr_of(Kernel::vaddr_t);