lld --oformat=binary not working with link script AT section attributes

[xiaoxiangmoe]

Reproduction https://github.com/xiaoxiangmoe/issue-llvm-lld-oformat-binary-compability

linker.ld:

ENTRY(main);
SECTIONS
{
    . = 0x7C00;
    .text : AT(0x7C00)
    {
        *(__start);
        _text = .;
        *(.text);
        _text_end = .;
    }
    .sig : AT(0x7DFE)
    {
        SHORT(0xaa55);
    }
} 

---

When using LLD without --oformat=binary

The result is

$ hexdump -C dist-lld-elf/boot.bin   
00000000  eb fe cc cc 00 00 00 00  00 00 00 00 00 00 00 00  |................|
00000010  00 00 00 00 00 00 00 00  00 00 00 00 00 00 00 00  |................|
*
000001f0  00 00 00 00 00 00 00 00  00 00 00 00 00 00 55 aa  |..............U.|
00000200

it works well

---

When using LLD with --oformat=binary

The result is

$ hexdump -C dist-lld-binary/boot.bin                                     
00000000  eb fe cc cc 55 aa                                 |....U.|
00000006

The AT section attribute is not working at all.