display: API for display driver
display: API for display driver

API for display drivers, supporting:
 * Turning on/off display blanking
 * Writing/Reading a bit map towards/from the display
 * Requesting framebuffer pointer
 * Setting display contrast and brightness
 * Querying display capabilities
 * Changing pixel format
 * Changing display orientation

Signed-off-by: Jan Van Winkel <d648848808a4d751aff880668aa63d2d9d94a5a4@dxplore.eu>

zephyrproject-rtos/zephyr,Vudentz/zephyr,explora26/zephyr,finikorg/zephyr,nashif/zephyr,punitvara/zephyr,ldts/zephyr,finikorg/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,punitvara/zephyr,finikorg/zephyr,nashif/zephyr,punitvara/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,ldts/zephyr,nashif/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,explora26/zephyr,explora26/zephyr,GiulianoFranchetto/zephyr,GiulianoFranchetto/zephyr,zephyrproject-rtos/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,Vudentz/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,punitvara/zephyr,punitvara/zephyr,galak/zephyr,explora26/zephyr,galak/zephyr,finikorg/zephyr,Vudentz/zephyr,finikorg/zephyr,nashif/zephyr,Vudentz/zephyr,ldts/zephyr