The implementation was attempting to capture the error using a scoped
variable reference, but the error value is already exposed via the
return value of `WaitForState()`. Using that instead fixes the data
race.
Fixes the following data race:
```
==================
WARNING: DATA RACE
Read by goroutine 74:
github.com/hashicorp/terraform/helper/resource.Retry()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/wait.go:35 +0x284
github.com/hashicorp/terraform/helper/resource.TestRetry_timeout()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/wait_test.go:35 +0x60
testing.tRunner()
/private/var/folders/vd/7l9ys5k57l91x63sh28wl_kc0000gn/T/workdir/go/src/testing/testing.go:456 +0xdc
Previous write by goroutine 90:
github.com/hashicorp/terraform/helper/resource.Retry.func1()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/wait.go:20 +0x87
github.com/hashicorp/terraform/helper/resource.(*StateChangeConf).WaitForState.func1()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/state.go:83 +0x284
Goroutine 74 (running) created at:
testing.RunTests()
/private/var/folders/vd/7l9ys5k57l91x63sh28wl_kc0000gn/T/workdir/go/src/testing/testing.go:561 +0xaa3
testing.(*M).Run()
/private/var/folders/vd/7l9ys5k57l91x63sh28wl_kc0000gn/T/workdir/go/src/testing/testing.go:494 +0xe4
main.main()
github.com/hashicorp/terraform/helper/resource/_test/_testmain.go:84 +0x20f
Goroutine 90 (running) created at:
github.com/hashicorp/terraform/helper/resource.(*StateChangeConf).WaitForState()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/state.go:127 +0x283
github.com/hashicorp/terraform/helper/resource.Retry()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/wait.go:34 +0x276
github.com/hashicorp/terraform/helper/resource.TestRetry_timeout()
/Users/phinze/go/src/github.com/hashicorp/terraform/helper/resource/wait_test.go:35 +0x60
testing.tRunner()
/private/var/folders/vd/7l9ys5k57l91x63sh28wl_kc0000gn/T/workdir/go/src/testing/testing.go:456 +0xdc
==================
```
Paul Hinze