Remove dummy PRIszX macros for formatting

Size specifiers are no longer needed now that we use typesafe tinyformat
for string formatting, instead of the system's sprintf.

No functional changes.

This continues the work in #3735.

src/walletdb.cpp

@@ -894,7 +894,7 @@ bool CWalletDB::Recover(CDBEnv& dbenv, std::string filename, bool fOnlyKeys)
         LogPrintf("Salvage(aggressive) found no records in %s.\n", newFilename);
         return false;
     }
-    LogPrintf("Salvage(aggressive) found %"PRIszu" records\n", salvagedData.size());
+    LogPrintf("Salvage(aggressive) found %u records\n", salvagedData.size());
 
     bool fSuccess = allOK;
     Db* pdbCopy = new Db(&dbenv.dbenv, 0);