samples: tfm_integration: Remove LPC55s69 tests

Removes lpcxpresso55s69_ns from certain sample.yaml files due
to changes required for TF-M 1.6.0 not being added to the
upstream project before the 1.6.0 release.

The NXP SDK available for download from NXP contains the required
updates, but these will need to be committed to TF-M, then made
available in the Zephyr fork, at which point the yaml files here can
have the LPC added back.

Signed-off-by: Kevin Townsend <kevin.townsend@linaro.org>