ANDROID: Use -fomit-frame-pointer for x86_ptrace_syscall_x86_64

do_full_int80() in ptrace_syscall.c uses bp register in inline
assembly. It doesn't work when frame pointer is not omitted.

After clang update, by default frame pointer isn't omitted
on x86_64. So explictly use -fomit-frame-pointer.

Bug: 352458178
Change-Id: I0b1f231d97e788c1597e3117d4a004be89fc8611
Signed-off-by: Edward Liaw <edliaw@google.com>

BUILD.bazel

@@ -1957,7 +1957,7 @@ cc_binary_with_abi(
         "x86_64",
         "x86",
     ],
-    copts = _KSELFTEST_COPTS,
+    copts = _KSELFTEST_COPTS + ["-fomit-frame-pointer"],
     includes = ["tools/testing/selftests"],
     linkopts = ["-static"],
     path_prefix = _KSELFTEST_DIR,