Disable icelake detection

Due some miscommunication upstream disabled all the icelake flags in the
current stable release.

The issue is tracked in rust-lang/rust#71473

src/cpu_features/x86.rs

@@ -44,14 +44,15 @@ impl Default for CpuFeatureLevel {
         && is_x86_feature_detected!("avx512vl")
     }
     fn avx512icl_detected() -> bool {
-      avx512_detected()
+      false
+      // avx512_detected()
         // && is_x86_feature_detected!("avx512bitalg")
         // && is_x86_feature_detected!("avx512clmulqdq")
-        && is_x86_feature_detected!("avx512ifma")
+        // && is_x86_feature_detected!("avx512ifma")
         // && is_x86_feature_detected!("avx512vaes")
-        && is_x86_feature_detected!("avx512vbmi")
+        // && is_x86_feature_detected!("avx512vbmi")
         // && is_x86_feature_detected!("avx512vbmi2")
-        && is_x86_feature_detected!("avx512vpopcntdq")
+        // && is_x86_feature_detected!("avx512vpopcntdq")
     }
 
     let detected: CpuFeatureLevel = if avx512icl_detected() {