Allow proper setCount SLAs across zones (#8752)

Fixes scenario where zones are appropriately
handled, along with supporting overriding set
count. The new fix also ensures that we handle
the various setup types properly.

Update documentation to properly indicate the
behavior.

Fixes #8750

Co-authored-by: Nitish Tiwari <nitish@minio.io>

cmd/setup-type.go

@@ -20,8 +20,11 @@ package cmd
 type SetupType int
 
 const (
+	// UnknownSetupType - starts with unknown setup type.
+	UnknownSetupType SetupType = iota
+
 	// FSSetupType - FS setup type enum.
-	FSSetupType SetupType = iota + 1
+	FSSetupType
 
 	// XLSetupType - XL setup type enum.
 	XLSetupType
@@ -45,5 +48,5 @@ func (setupType SetupType) String() string {
 		return globalMinioModeGatewayPrefix
 	}
 
-	return ""
+	return "unknown"
 }