[boot] Go back to loading symbol table in boot

The symbol table needs to be passed to the panic handler very early in
the kernel, loading it in init is far less useful. Return it to the boot
directory and remove it from the initrd.

src/user/srv.init/loader.cpp

@@ -46,7 +46,7 @@ load_program(
 {
     uintptr_t base_address = reinterpret_cast<uintptr_t>(data.pointer);
 
-    elf::file progelf {data.pointer, data.count};
+    elf::file progelf {data};
 
     if (!progelf.valid()) {
         sprintf(err_msg, "  ** error loading program '%s': ELF is invalid", name);
@@ -72,7 +72,7 @@ load_program(
         return false;
     }
 
-    for (auto &seg : progelf.programs()) {
+    for (auto &seg : progelf.segments()) {
         if (seg.type != elf::segment_type::load)
             continue;