[boot] Load programs in boot, not kernel

Remove ELF and initrd loading from the kernel. The bootloader now loads
the initial programs, as it does with the kernel. Other files that were
in the initrd are now on the ESP, and non-program files are just passed
as modules.

src/kernel/scheduler.h

@@ -41,10 +41,11 @@ public:
 	scheduler(lapic *apic);
 
 	/// Create a new process from a program image in memory.
-	/// \arg name  Name of the program image
-	/// \arg data  Pointer to the image data
+	/// \arg phys  Physical address of the loaded program image
+	/// \arg virt  Virtual address of the loaded program image
 	/// \arg size  Size of the program image, in bytes
-	void load_process(const char *name, const void *data, size_t size);
+	/// \arg entry Virtual address of the program entrypoint
+	void load_process(uintptr_t phys, uintptr_t virt, size_t size, uintptr_t entry);
 
 	/// Create a new kernel task
 	/// \arg proc     Function to run as a kernel task