Set pinmux_emmc_pins mux mode for cmd line to MODE2 in order
to detect eMMC on BBB and BBW + eMMC cape.
Signed-off-by: NBalaji T K <balajitk@ti.com>
Tested-by: NFelipe Balbi <balbi@ti.com>
Signed-off-by: NBenoit Cousson <bcousson@baylibre.com>