[llvm] [HashRecognize] Clarify hdr comment on GF(2^m) (NFC) (PR #157482)

[Piotr Fusik via llvm-commits]

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@@ -24,9 +24,8 @@
 //
 //    c_m * x^m + c_(m-1) * x^(m-1) + ... + c_0 * x^0
 //
-// where each coefficient c is can take values in GF(2^n), where 2^n is termed
-// the order of the Galois field. For GF(2), each coefficient can take values
-// either 0 or 1, and the polynomial is simply represented by m+1 bits,
+// where each coefficient c is can take values 0 or 1, and 2^n is termed the
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pfusik wrote:

I don't see what `2^n` refers to?

https://github.com/llvm/llvm-project/pull/157482