imx6_is_bmode_from_gpr9 always returns false, because
IMX6_SRC_GPR10_BMODE is 1<<28 and gets casted to u8 on return.
This moves the function body into imx6_src_get_boot_mode, since that is the
only one using it and it is on the same abstraction level (accessing
registers directly).
Signed-off-by: Claudius Heine <ch@denx.de>
e01c8cfe57