Integrate u-boot-seco-imx/ektor5/a62-hdmi-gpu

Commit: https://git.seco.com/arm/nxp/imx/develop/yocto/5.x/u-boot-seco-imx/-/commit/a6c7b43658f3a29d2ca753035ba837761c8fd071

[A62][ENV] Add bpp specification to HDMI

This videomode spec is required for GPU to visualize correctly framebuffer accelerated applications.

Signed-off-by: Ettore Chimenti ettore.chimenti@seco.com