MLK-18333-2 imx8m: add QSPI boot dev

When boot type could not be detected from rom sw info,
read sbmr1 to detect, here we only use it to detect FLEXSPI
boot, because ROM not update it in rom sw info.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
(cherry picked from commit 3735aedbf6dbebfac830089618ca334c419f43bd)
(cherry picked from commit 8324d0f37a3dc8c2516dad439aa6b91d77eebcbc)
2 files changed