rtl_bt: Add firmware and configuration files for RTL8822C BT UART chip

The firmware and config files are for RTL8822C BT controller with UART interface.
Version: 0x0599_0D54
Signed-off-by: Hilda Wu <hildawu@realtek.com>
Signed-off-by: Josh Boyer <jwboyer@kernel.org>

WHENCE

@@ -3423,6 +3423,8 @@ File: rtl_bt/rtl8821c_fw.bin
 File: rtl_bt/rtl8821c_config.bin
 File: rtl_bt/rtl8822cu_fw.bin
 File: rtl_bt/rtl8822cu_config.bin
+File: rtl_bt/rtl8822cs_fw.bin
+File: rtl_bt/rtl8822cs_config.bin
 
 Licence: Redistributable. See LICENCE.rtlwifi_firmware.txt for details.