`GetParityForSC` has a value receiver, so Config is copied before the lock is obtained.
Make it pointer receiver.
Fixes:
```
WARNING: DATA RACE
Read at 0x0000079cdd10 by goroutine 190:
github.com/minio/minio/cmd.(*erasureServerPools).BackendInfo()
github.com/minio/minio/cmd/erasure-server-pool.go:579 +0x6f
github.com/minio/minio/cmd.(*erasureServerPools).LocalStorageInfo()
github.com/minio/minio/cmd/erasure-server-pool.go:614 +0x3c6
github.com/minio/minio/cmd.(*peerRESTServer).LocalStorageInfoHandler()
github.com/minio/minio/cmd/peer-rest-server.go:347 +0x4ea
github.com/minio/minio/cmd.(*peerRESTServer).LocalStorageInfoHandler-fm()
...
WARNING: DATA RACE
Read at 0x0000079cdd10 by goroutine 190:
github.com/minio/minio/cmd.(*erasureServerPools).BackendInfo()
github.com/minio/minio/cmd/erasure-server-pool.go:579 +0x6f
github.com/minio/minio/cmd.(*erasureServerPools).LocalStorageInfo()
github.com/minio/minio/cmd/erasure-server-pool.go:614 +0x3c6
github.com/minio/minio/cmd.(*peerRESTServer).LocalStorageInfoHandler()
github.com/minio/minio/cmd/peer-rest-server.go:347 +0x4ea
github.com/minio/minio/cmd.(*peerRESTServer).LocalStorageInfoHandler-fm()
```
This is to ensure that there are no projects
that try to import `minio/minio/pkg` into
their own repo. Any such common packages should
go to `https://github.com/minio/pkg`