[LLD][COFF] Add support for custom section layout (#152779)
MS link.exe provides the `/sectionlayout:@` option to specify the order
of output sections at the granularity of individual sections. LLD/COFF
currently does not have capability for user-controlled ordering of one
or more output sections (as LLD/COFF does not support linker scripts),
and this PR adds the option to align with MS link.exe.
The option accepts only a file that specifies the order of sections, one
per line. For example, `mylayout.txt` could emit the `.text` section
after all other sections while preserving the original relative order of
the remaining sections.
```
.data
.rdata
.pdata
.rsrc
.reloc
.text
```
```bash
echo 'int main() { return 0; }' > main.c
cl main.c /link /entry:main /sectionlayout:@mylayout.txt
llvm-readobj --sections main.exe
```
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