Move secp256k1_ecmult_odd_multiples_table_globalz_windowa and fix docs #1035

1. 
   real-or-random commented at 10:18 am on December 7, 2021: contributor

   secp256k1_ecmult_odd_multiples_table_globalz_windowa is in the wrong module. This function had been used within ecmult in the past but since 8c1c831bdb083dfa8b50fac16a0e17a7e1df4064, it is only used in ecmult_const. This also means its comment is wrong.

   Originally posted by @real-or-random in #942 (comment)

2. siv2r cross-referenced this on Dec 23, 2021 from issue ecmult: move `_ecmult_odd_multiples_table_globalz_windowa` by siv2r
3. real-or-random closed this on Dec 24, 2021

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