build: update btcwallet to point to latest version

Gopkg.lock

@@ -120,7 +120,7 @@
   revision = "ab6388e0c60ae4834a1f57511e20c17b5f78be4b"
 
 [[projects]]
-  digest = "1:a9bb59675f2aa863eff2bab6f0668b5e6feacaf6b7978fe5a654b068d5ca8e36"
+  digest = "1:04bf3f47dafa64588795c5e0329dc662e867c3afa191051821dbacbe09ba2ca8"
   name = "github.com/btcsuite/btcwallet"
   packages = [
     "chain",
@@ -140,7 +140,7 @@
     "wtxmgr",
   ]
   pruneopts = "UT"
-  revision = "1ede0a1a66bad8f7db796615e496a0a0faba5182"
+  revision = "5fb94231d0c814f02ffc3110eee588278151b4e1"
 
 [[projects]]
   branch = "master"

Gopkg.toml

@@ -72,7 +72,7 @@
 
 [[constraint]]
   name = "github.com/btcsuite/btcwallet"
-  revision = "1ede0a1a66bad8f7db796615e496a0a0faba5182"
+  revision = "5fb94231d0c814f02ffc3110eee588278151b4e1"
 
 [[constraint]]
   name = "github.com/tv42/zbase32"