Make linter happy by changing if-else chain to a switch.

More background on this can be found in [1]. In short: Go's switch
statement is kinda different to C's (or Java's, f.e.) and can (or
should, as it is idiomatic Go) be used instead of if-else chains.

[1] https://golang.org/doc/effective_go.html#switch

cmd/aws-cli-oidc/main.go

@@ -40,17 +40,18 @@ Options:
  log.Fatalf("%v\n", err)
  }
 
- if conf.GetCred {
+ switch {
+ case conf.GetCred:
  err := internal.GetCred(conf.ProviderName, conf.RoleARN)
  if err != nil {
  log.Fatalf("Error during get-cred: %v\n", err)
  }
- } else if conf.Setup {
+ case conf.Setup:
  err := internal.RunSetup(conf.ProviderName)
  if err != nil {
  log.Fatalf("Error during setup: %v\n", err)
  }
- } else if conf.Cache {
+ case conf.Cache:
  if conf.Show {
  output, err := internal.CacheShow()
  if err != nil {