Fix up/ignore failing ui tests on fuchsia

Author: tmandry

src/test/ui/intrinsics/intrinsic-alignment.rs

@@ -14,6 +14,7 @@ mod rusti {
           target_os = "dragonfly",
           target_os = "emscripten",
           target_os = "freebsd",
+          target_os = "fuchsia",
           target_os = "linux",
           target_os = "macos",
           target_os = "netbsd",

src/test/ui/issues/issue-70093.rs

@@ -1,6 +1,7 @@
 // run-pass
 // compile-flags: -Zlink-native-libraries=no -Cdefault-linker-libraries=yes
 // ignore-windows - this will probably only work on unixish systems
+// ignore-fuchsia - missing __libc_start_main for some reason (#84733)
 
 #[link(name = "some-random-non-existent-library", kind = "static")]
 extern "C" {}

src/test/ui/structs-enums/rec-align-u64.rs

@@ -35,6 +35,7 @@ struct Outer {
           target_os = "dragonfly",
           target_os = "emscripten",
           target_os = "freebsd",
+          target_os = "fuchsia",
           target_os = "linux",
           target_os = "macos",
           target_os = "netbsd",

src/test/ui/x86stdcall.rs

@@ -27,6 +27,7 @@ pub fn main() {
           target_os = "dragonfly",
           target_os = "emscripten",
           target_os = "freebsd",
+          target_os = "fuchsia",
           target_os = "linux",
           target_os = "macos",
           target_os = "netbsd",