[btcsuite/btcd] 9f71f0: txscript: Drop the mutex before doing crypto

[David Hill]

  Branch: refs/heads/master
  Home:   https://github.com/btcsuite/btcd
  Commit: 9f71f090e675f7f8389cf147620a21be726d18af
      
https://github.com/btcsuite/btcd/commit/9f71f090e675f7f8389cf147620a21be726d18af
  Author: David Hill <dh...@mindcry.org>
  Date:   2017-01-31 (Tue, 31 Jan 2017)

  Changed paths:
    M txscript/sigcache.go

  Log Message:
  -----------
  txscript: Drop the mutex before doing crypto