vbe: Support selecting images based on phase in FIT

With SPL we want to specify the phase of the image to be loaded. Add
support for this.

This is the implementation of a FIT feature added to the spec a few
years ago and entails a small code-size increase, about 70 bytes on
Thumb2.

Signed-off-by: Simon Glass <sjg@chromium.org>
Link: https://docs.u-boot.org/en/latest/usage/fit/index.html
1 file changed