As __start must be placed at a precise location, a separate, explicit
input section is needed to guarantee this.
Why is this an issue ? NuttX uses --entry=__start which puts __start in
its correct location, but out-of-tree builds won't work, so it more robust
to use an explicit section for the startup code and enforce its placement
in the linker script.
Adds board definition for imx93-evk board
- Support for the Cortex-A55 core in i.MX93, support for the Cortex-M33
core is _not_ provided
- "nsh" profile is provided, this includes a minimalistic feature set
which boots the SoM to nsh console
- A bootloader is required, u-boot has been tested
