Build HELLO page tables from unused memory instead of scratch buffer

src/hulk/bootinfo.d

@@ -33,6 +33,7 @@ struct BootInfo
         enum Type
         {
             Reserved,
+            Bootloader,
             Conventional,
             Unusable,
             ACPIReclaim,
@@ -68,12 +69,6 @@ struct BootInfo
     /* Physical address of stack while jumping to HULK. */
     ulong stack_phys;
 
-    /* Physical address of page tables while jumping to HULK. */
-    ulong pt_phys;
-
-    /* Size of page tables while jumping to HULK. */
-    ulong pt_size;
-
     /* Physical address of ACPI XSDT table. */
     ulong acpi_xsdt_phys;
 }