Measure EVS FX/FL with MLD, SSNR and MAX ABS DIFF

This is a task to measure the EVS FX encoder vs EVS FL decoder, by decoding with EVS FL decoder and applying our suite of test tools to the decoded output: MLD, SSNR, MAX ABS DIFF and PEAQ.

The idea is to run this using the 26.444 test vectors set.

⚠️ If you want to replicate this test, please note that you need to change the order of ref and test in the call to cmp_pcm in test_26444.py. The reason is that you want to use the 26.444 test vectors as test signal, and the floating point code as reference. ⚠️