Fixed the following golint warnings:
./cmd/fpga_plugin/fpga_plugin.go:71:2: struct field fpgaId should be fpgaID
./cmd/fpga_plugin/fpga_plugin.go:78:44: func parameter fpgaId should be fpgaID
./cmd/fpga_plugin/fpga_plugin.go:104:8: var interfaceId should be interfaceID
./cmd/fpga_plugin/fpga_plugin.go:120:7: var interfaceIdFile should be interfaceIDFile
./cmd/fpga_plugin/fpga_plugin.go:156:8: range var fpgaId should be fpgaID
./cmd/fpga_plugin/fpga_plugin.go:254:6: range var fpgaId should be fpgaID
./cmd/fpga_plugin/fpga_plugin.go:254:14: should omit 2nd value from range; this loop is equivalent to `for fpgaId := range ...`
./internal/deviceplugin/deviceplugin.go:30:6: exported type DeviceInfo should have comment or be unexported
./internal/deviceplugin/deviceplugin.go:35:6: exported type Server should have comment or be unexported
./internal/deviceplugin/deviceplugin.go:39:1: exported method Server.Serve should have comment or be unexported
./internal/deviceplugin/deviceplugin.go:43:1: exported method Server.Stop should have comment or be unexported