Only minor changes are required to make the kernel 64 bit compatible.
Most of the changes are either DEBUG/printf formatting or different types for void pointer casting.

The only other change is the type of the `data` member in priority_queue_node_t, as `data` must be able to store a pointer.
For current architectures, the assumption `sizeof(unsigned int) == sizeof(void *)` holds, but not for 64 bit.
Therefore, the type is changed to `uintptr_t', which has the same size for the current architectures, but can also store a pointer in 64 bits.

* priority_queue_t: Replaced `-1U` literal with PRIORITY_QUEUE_DATA_SIGNALING define
* architecture.h: Added 64-bit
* bloom.h: Fixed typedef for the hashfp_t function pointer
* vfs.h: Increased default vfs buffer sizes for 64 bit
* bytes.h: Check if socklen_t is already defined
* ztimer: Use PRIxPTR format specifier