SE-0483: `InlineArray` Literal Syntax

[benrimmington]

@ksluder

In the absence of this sugar, can the compiler still correctly type-check inline arrays initialized from array literals, including for their cardinality?

The test/Sema/inlinearray.swift file contains examples of type-checking.

There was a recent discussion about non-literal integer generics.

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@GreatApe

Does not feel serious

LLVM arrays use a similar syntax.