Math.ScaleB documentation is incorrect.

[Jabbl]

dotnet/runtime#42476 seems to have moved ScaleB from a C-runtime call to a managed implementation.
The documentation, however, still has a remark that the underlying C runtime is called.

Since this is no longer the case, the remark should probably be removed.

[dotnet-issue-labeler]

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[dotnet-policy-service]

Tagging subscribers to this area: @dotnet/area-system-numerics

[tannergooding]

The exact remark should probably be something implying “may” rather than “does”.

There are many possible runtimes and a valid implementation of ScaleB may defer into the C runtime, be an intrinsic to the JIT/AOT, or rely on other behavior