Add comments explaining the redfish SetVirtualMedia method

internal/redfishwrapper/virtual_media.go

@@ -8,7 +8,7 @@ import (
 	rf "github.com/stmcginnis/gofish/redfish"
 )
 
-// Set the boot device for the system.
+// Set the virtual media attached to the system, or just eject everything if mediaURL is empty.
 func (c *Client) SetVirtualMedia(ctx context.Context, kind string, mediaURL string) (ok bool, err error) {
 	managers, err := c.Managers(ctx)
 	if err != nil {
@@ -44,6 +44,8 @@ func (c *Client) SetVirtualMedia(ctx context.Context, kind string, mediaURL stri
 		}
 	}
 
+	// An empty mediaURL means eject everything, so if that's the case we're done. Otherwise, we
+	// need to insert the media.
 	if mediaURL != "" {
 		setMedia := false
 		for _, manager := range managers {