Backend refactor (#120)

* remove spqlios, split cpu_ref and cpu_avx into different crates

* remove spqlios submodule

* update crate naming & add avx tests

poulpy-cpu-avx/benches/vec_znx.rs

@@ -0,0 +1,26 @@
+// poulpy-backend/benches/vec_znx_add.rs
+use criterion::{Criterion, criterion_group, criterion_main};
+use poulpy_cpu_avx::FFT64Avx;
+use poulpy_hal::reference::vec_znx::{bench_vec_znx_add, bench_vec_znx_automorphism, bench_vec_znx_normalize_inplace};
+
+#[allow(dead_code)]
+fn bench_vec_znx_add_cpu_avx_fft64(c: &mut Criterion) {
+    bench_vec_znx_add::<FFT64Avx>(c, "FFT64Avx");
+}
+
+#[allow(dead_code)]
+fn bench_vec_znx_normalize_inplace_cpu_avx_fft64(c: &mut Criterion) {
+    bench_vec_znx_normalize_inplace::<FFT64Avx>(c, "FFT64Avx");
+}
+
+fn bench_vec_znx_automorphism_cpu_avx_fft64(c: &mut Criterion) {
+    bench_vec_znx_automorphism::<FFT64Avx>(c, "FFT64Avx");
+}
+
+criterion_group!(
+    benches,
+    bench_vec_znx_add_cpu_avx_fft64,
+    bench_vec_znx_normalize_inplace_cpu_avx_fft64,
+    bench_vec_znx_automorphism_cpu_avx_fft64,
+);
+criterion_main!(benches);