Allow a couple more swab implementation details through.

We hadn't spotted these before because no-one's using them, but C23 makes
the use of undeclared identifiers (in the also-unused caller) an error.

Change-Id: Iad5f364424e5621280d679aa2530e0e872abbb85
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 06afb25..a71318e 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -133,6 +133,9 @@
           # These are required to support the above functions.
           "__fswahw32",
           "__fswahb32",
+          # As are these, for ILP32.
+          "__arch_swab32",
+          "__arch_swab64",
           # This is used by various macros in <linux/ioprio.h>.
           "ioprio_value",