feat(pl/ke): initial amd64 support

build/linker-scripts/x86_64.lds

@@ -44,6 +44,12 @@ SECTIONS
         *(.rodata .rodata.*)
     } :rodata
 
+    .percpu_init_array : {
+        __init_array_percpu_start = .;
+        KEEP(*(.percpu_init_array))
+        __init_array_percpu_end = .;
+    } :rodata
+
     /* Add a .note.gnu.build-id output section in case a build ID flag is added to the */
     /* linker command. */
     .note.gnu.build-id : {
@@ -57,6 +63,12 @@ SECTIONS
         *(.data .data.*)
     } :data
 
+    .data.percpu : {
+        __percpu_start = .;
+        *(.data.percpu)
+        __percpu_end = .;
+    } :data
+
     /* NOTE: .bss needs to be the last thing mapped to :data, otherwise lots of */
     /* unnecessary zeros will be written to the binary. */
     /* If you need, for example, .init_array and .fini_array, those should be placed */