Hi everyone

I'd like to request for comment on some changes to the TF-M installed files. Since this is an interface change (though minor), changes to it might cause issues with existing TF-M integrations.

The current install directory looks like:

install ├── export │   └── tfm └── outputs

This doesn't give any useful information about what is contained in each directory. The proposed replacement is:

install ├── image_signing ├── interface └── outputs

Where the contents of `export/tfm` have been moved into `interface`, which better captures the contents of that directory.

`image_signing` is new in the patchset, and contains the scripts, layouts and keys needed to sign an NS image.

The final improvement in the patchset is the ability to control the location of the `install` directory via TFM_INSTALL_PATH which could be useful for integrators.

Feedback would be appreciated if you feel that these new directory names could be improved, or if this change would cause significant breakage for your TF-M integration.

Patchset here: https://review.trustedfirmware.org/c/TF-M/trusted-firmware-m/+/7398/6

Raef