ext: simplelink: Update cc32xx SDK to version 1.50.00.06

This includes:
- peripheral drivers
- driverlib (HAL)
- WiFi host driver and porting layer interface headers

See README in this patch for details.

Origin: Texas Instruments cc32xx SimpleLink SDK
URL: http://www.ti.com/tool/download/SIMPLELINK-CC3220-SDK


Purpose: Provide driver libraries and HAL for TI CC32XX SoC
Maintained-by: External

Signed-off-by: Gil Pitney <gil.pitney@linaro.org>