ignore some targets

Author: RalfJung

src/test/ui/intrinsics/panic-uninitialized-zeroed.rs

@@ -2,6 +2,8 @@
 // revisions: default strict
 // [strict]compile-flags: -Zstrict-init-checks
 // ignore-tidy-linelength
+// ignore-emscripten spawning processes is not supported
+// ignore-sgx no processes
 
 // This test checks panic emitted from `mem::{uninitialized,zeroed}`.