LoongArch: vmlinux.lds.S: Add missing ELF_DETAILS

Commit c604abc3 ("vmlinux.lds.h: Split ELF_DETAILS from STABS_DEBUG")
splits ELF_DETAILS from STABS_DEBUG, resulting in missing ELF_DETAILS
information in LoongArch architecture, so add it.

Fixes: c604abc3

 ("vmlinux.lds.h: Split ELF_DETAILS from STABS_DEBUG")
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>