feat: add support for aarch64 timer/interrupts, port MontaukOS userspace

programs/link.ld

@@ -3,11 +3,10 @@
     * Linker script for MontaukOS userspace programs
     * Copyright (c) 2025 Daniel Hammer
     *
-    * Programs are loaded at a standard user-space address.
+    * Programs are loaded at a standard user-space address. The output
+    * format is the toolchain's default (x86_64-montauk or aarch64-montauk).
 */
 
-OUTPUT_FORMAT(elf64-x86-64)
-
 ENTRY(_start)
 
 SECTIONS