Embedded builtins disabled by default on AIX

https://bugs.chromium.org/p/v8/issues/detail?id=8043

Bug: v8:8043
Change-Id: Ia671e6ebf9dad7379f57bf55ce47cc6cd12809b6
Reviewed-on: https://chromium-review.googlesource.com/1168085
Commit-Queue: John Barboza <jbarboza@ca.ibm.com>
Reviewed-by: John Barboza <jbarboza@ca.ibm.com>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55061}

BUILD.gn

@@ -74,7 +74,8 @@ declare_args() {
   # Enable embedded builtins.
   # TODO(jgruber,v8:6666): Support ia32 and maybe MSVC.
   v8_enable_embedded_builtins =
-      v8_use_snapshot && v8_current_cpu != "x86" && (!is_win || is_clang)
+      v8_use_snapshot && v8_current_cpu != "x86"
+          && !is_aix && (!is_win || is_clang)
 
   # Enable code-generation-time checking of types in the CodeStubAssembler.
   v8_enable_verify_csa = false