scripted-diff: Replace UINT256_ONE() with uint256::ONE

-BEGIN VERIFY SCRIPT-
sed -i '/inline.* UINT256_ONE() {/,+1d' src/uint256.h
sed -i 's/UINT256_ONE()/uint256::ONE/' $(git grep -l UINT256_ONE)
-END VERIFY SCRIPT-

src/test/sighash_tests.cpp

@@ -28,7 +28,7 @@ uint256 static SignatureHashOld(CScript scriptCode, const CTransaction& txTo, un
 {
     if (nIn >= txTo.vin.size())
     {
-        return UINT256_ONE();
+        return uint256::ONE;
     }
     CMutableTransaction txTmp(txTo);
 
@@ -58,7 +58,7 @@ uint256 static SignatureHashOld(CScript scriptCode, const CTransaction& txTo, un
         unsigned int nOut = nIn;
         if (nOut >= txTmp.vout.size())
         {
-            return UINT256_ONE();
+            return uint256::ONE;
         }
         txTmp.vout.resize(nOut+1);
         for (unsigned int i = 0; i < nOut; i++)