Fix ARM Chrome not starting up.

The seccomp bpf filter was complaining because getsockopt and setsockopt were being called but they're not allowed. I had fixed this for x86-64 in r360114 but the change should have also allowed ARM. Really, it's anything other than 32 bit Linux (which doesn't have a specific id for these methods).

BUG=572795,561803

Review URL: https://codereview.chromium.org/1553543002

Cr-Commit-Position: refs/heads/master@{#367102}

sandbox/linux/seccomp-bpf-helpers/baseline_policy.cc

@@ -231,7 +231,7 @@ ResultExpr EvaluateSyscallImpl(int fs_denied_errno,
     return RestrictSocketcallCommand();
 #endif
 
-#if defined(__x86_64__)
+#if !defined(__i386__)
   if (sysno == __NR_getsockopt || sysno ==__NR_setsockopt) {
     // Used by Mojo EDK to catch a message pipe being sent over itself.
     const Arg<int> level(1);

sandbox/linux/seccomp-bpf-helpers/baseline_policy_unittest.cc

@@ -335,7 +335,7 @@ BPF_DEATH_TEST_C(BaselinePolicy,
   clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
 }
 
-#if defined(__x86_64__)
+#if !defined(__i386__)
 BPF_DEATH_TEST_C(BaselinePolicy,
                  GetSockOptWrongLevelSigsys,
                  DEATH_SEGV_MESSAGE(sandbox::GetErrorMessageContentForTests()),