Integrate u-boot-seco-imx/seco/develop_ym

Commit: https://git.seco.com/edgehog/bsp/nxp/u-boot-seco-imx/-/commit/50e34a3b78b61351496797da4922f7bd9d5d6dc4

Merge branch 'seco_lf_v2021.04' of https://git.seco.com/edgehog/bsp/nxp/u-boot-seco-imx into seco/develop_ym

--

Commit: https://git.seco.com/edgehog/bsp/nxp/u-boot-seco-imx/-/commit/bf13288415913f080eedc54e9529d14ca40ddafe

[SECO-CONFIG] fix compilation without FTD overlays