Use imx6_src_get_boot_mode() instead of manually reading SBMR1. The
existing function has proper handling for software overrides of the
bootdevice which can happen, for example, when booting from an alternate
source using `bmode`.
Signed-off-by: Harald Seiler <hws@denx.de>
Reviewed-by: Fabio Estevam <festevam@gmail.com>
12f9b4d086