[U-Boot] Add mikroBUS flash click support to the imx7

In-Reply-To:

Add support for the "flash click" and probably other SPI mikroBUS click boards on i.MX7 Sabre evaluation board.

board/freescale/mx7dsabresd/mx7dsabresd.c | 24 ++++++++++++++++++++++++ configs/mx7dsabresd_secure_defconfig | 2 ++ drivers/mtd/spi/sf_params.c | 1 + include/configs/mx7dsabresd.h | 4 ++++ 4 files changed, 31 insertions(+)