manifest: Upgrade to trusted-firmware-m 1.8.0

Update trusted-firmware-m to 1.8.0, mbedtls to 3.4.0, and tf-m-tests to
1.8.0.  Includes minor cmake changes due to file renames and such, as well
as adjusting the return type of a callback function that has changed since
the previous version of trusted-firmware-m.

Signed-off-by: David Brown <david.brown@linaro.org>