[llvm] [llvm-ar] --help: fix unquoted angle bracket (PR #101364)

[James Henderson via llvm-commits]

jh7370 wrote:

> > In this case, < is intended to represent the "read stdin from file" indicator.
> 
> I've readded it now with a space, so I guess the syntax would be `[-M < mri-script]`

No, it should be `-M [< mri-script]`. The tool prints two possible invocations, the first, not touched by this patch, is the "regular" style where you e.g. add files to an archive using something like `llvm-ar rc archive.a obj.o`. The second line is for using MRI style. The MRI style is only activated when `-M` is specified, so the `-M` in that case in compulsory.

https://github.com/llvm/llvm-project/pull/101364