[lld] [LLD][COFF] allow saving intermediate files with /lldsavetemps (PR #115131)

[Miguel A. Arroyo via llvm-commits]

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@@ -79,6 +79,9 @@ def lldltocachepolicy : P<"lldltocachepolicy",
     "Pruning policy for the ThinLTO cache">;
 def lldsavetemps : F<"lldsavetemps">,
     HelpText<"Save intermediate LTO compilation results">;
+def lldsavetemps_eq : Joined<["/", "-", "/?", "-?"], "lldsavetemps:">,
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mayanez wrote:

It seems `_colon` is used for `manifest_colon`. It probably makes sense to use `_colon` here as well. 

https://github.com/llvm/llvm-project/pull/115131