Merge bitcoin#15618: refactor: Remove unused function

fa5c511 refactor: Remove unused function (MarcoFalke)

Pull request description:

  Oversight of kallewoof and mine in bitcoin#13541 (comment)

Tree-SHA512: 2fd3c4ecde5d3c58b113aa58d606976ceb4998358bde0547ead8e83df210722fa9821d2c88b717bdd190ef71593cd9c0154c3a5d3f2ccc3af8cbf6c36aaa6d45

Author: laanwj

src/validation.cpp

@@ -3159,26 +3159,6 @@ static int GetWitnessCommitmentIndex(const CBlock& block)
     return commitpos;
 }
 
-// Compute at which vout of the block's coinbase transaction the signet
-// signature occurs, or -1 if not found.
-static int GetSignetSignatureIndex(const CBlock& block)
-{
-    if (!block.vtx.empty()) {
-        for (size_t o = 0; o < block.vtx[0]->vout.size(); o++) {
-            if (block.vtx[0]->vout[o].scriptPubKey.size() >= 68     // at minimum 64 byte signature plus script/header data
-             && block.vtx[0]->vout[o].scriptPubKey[0] == OP_RETURN  // unspendable
-             && block.vtx[0]->vout[o].scriptPubKey[1] == block.vtx[0]->vout[o].scriptPubKey.size() - 1 // push the rest
-             && block.vtx[0]->vout[o].scriptPubKey[2] == 0xec       // 's' ^ 0x9f
-             && block.vtx[0]->vout[o].scriptPubKey[3] == 0xc7       // 'i' ^ 0xae
-             && block.vtx[0]->vout[o].scriptPubKey[4] == 0xda       // 'g' ^ 0xbd
-             && block.vtx[0]->vout[o].scriptPubKey[5] == 0xa2) {    // 'n' ^ 0xcc
-                return (int)o;
-            }
-        }
-    }
-    return -1;
-}
-
 void UpdateUncommittedBlockStructures(CBlock& block, const CBlockIndex* pindexPrev, const Consensus::Params& consensusParams)
 {
     int commitpos = GetWitnessCommitmentIndex(block);