usd: initial addition, Boundary Devices board

usd: add CONFIG_CMD_GPIO
usd: explicit fbp_detect_i2c
usd: use boundary.h
usd: add CONFIG_SPI_FLASH_SPANSION
usd: usd_defconfig add CONFIG_BLOCK_CACHE
usd: use common code for eth init
usd: eth.c now in common directory
usd: move misc_init_r/do_kbd to common
usd: move mmc_init/ dram_init/ overwrite_console/ common_board_init/ splash_screen_prepare/ board_cfb_skip to common
usd: use common 1066mhz_4x128mx16.cfg
usd: add  CONFIG_SPI_FLASH_GIGADEVICE: to defconfigs
usd: use common ddr script
usd: port to v2018.07

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

usd: update to v2017.01
usd: update to v2017.03

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

usd.c: Add M101NWWB as the default detected LVDS display

Signed-off-by: Ian Coolidge <ian@boundarydevices.com>