cad: initial addition, Boundary Devices board

cad.h: CONFIG_IPUV3_CLK 264000000
cad: add CONFIG_CMD_GPIO
cad: explicit fbp_detect_i2c
cad: use VDF_SPI_QVGA
cad: use boundary.h
cad: setup rgb_gpio_pads in board_early_init_f
cad: add CONFIG_SPI_FLASH_SPANSION
cad: cad_defconfig add CONFIG_BLOCK_CACHE
cad: use common code for eth init
cad: eth.c now in common directory
cad: move misc_init_r/do_kbd to common
cad: move mmc_init/ dram_init/ overwrite_console/ common_board_init/ splash_screen_prepare/ board_cfb_skip to common
cad: add  CONFIG_SPI_FLASH_GIGADEVICE: to defconfigs
cad: use common ddr script
cad: port to v2018.07

Signed-off-by: Troy Kisky <troy.kisky@boundarydevices.com>

cad: update to v2017.01
cad: update to v2017.03

Signed-off-by: Gary Bisson <gary.bisson@boundarydevices.com>