[TF-M] Recent patches

I have just pushed a simple one liner for tools/tfm_parse_manifest_list.py, which keeps the generated #include file names using unix style paths, even if the files were generated on windows.

In the past I have manually fixed up the paths on the generated #include lines in some of the files, but got bored and fixed the script instead.

https://review.trustedfirmware.org/c/trusted-firmware-m/+/3605

I also pushed a major (80 files) fix last night that cleans up most of the warnings when building with the IAR toolkit, which for now has more warnings enabled than ARMCLANG and GNUARM. This should make it easier to enable "pedantic" mode with GNUARM as well.

https://review.trustedfirmware.org/c/trusted-firmware-m/+/3594

Thomas