moving efi code to boot

build.zig

@@ -99,10 +99,13 @@ pub fn build(b: *std.Build) void {
 
     b.installArtifact(exe);
 
+    // Boot methods live in src/boot/, one per way of getting the kernel running.
+    // Each is its own binary/entry (a loader is built for its own target); today
+    // that's UEFI for x86-64, with room for e.g. a device-tree path for the Pis.
     const efiexe = b.addExecutable(.{
         .name = "BOOTX64",
         .root_module = b.createModule(.{
-            .root_source_file = b.path("src/efi.zig"),
+            .root_source_file = b.path("src/boot/efi.zig"),
             .target = b.resolveTargetQuery(.{
                 .cpu_arch = .x86_64,
                 .os_tag = .uefi,