Fix an error introduced into stm32_pwr_enablebkp().  That function must preserve the previous state of backup domain access on return.

STM32F429i Disco: (1) Fix a bad return value if the LCD driver is already initialized. (2) The LCD driver initialization is now performed during the early boot sequence.  (3) Increased the size of the message queue from 32 to 64 in the lcd configuration.  From Marco, ocram.lhark@yahoo.com.

Add support for the new DMA2D features to the STM32F429i-Disco LTDC configuration.  From Marco Krahl.

Remove all traces of the Galileo board.  That port is not going to happen -- I dont' even have the Galileo board anymore.

More renaming: up_lcdinitialize->board_lcd_initialize, up_lcdgetdev->board_lcd_getdev, up_lcduninitialize->board_lcd_uninitialize