Three-wire UART (H5) protocol support

configname: CONFIG_BT_HCIUART_3WIRE

Linux Kernel Configuration
└─>Networking support
└─>Bluetooth subsystem support
└─>Bluetooth device drivers
└─>Three-wire UART (H5) protocol support
In linux kernel since version 3.1 (release Date: 2011-10-24)  
The HCI Three-wire UART Transport Layer makes it possible to
user the Bluetooth HCI over a serial port interface. The HCI
Three-wire UART Transport Layer assumes that the UART
communication may have bit errors, overrun errors or burst
errors and thereby making CTS/RTS lines unnecessary.

Say Y here to compile support for Three-wire UART protocol.