VS2022 fails with "error C7631: 'info': variable with internal linkage
declared but not defined" because Iguana's type info was not defined.
Moved globals out of internal linkage to fix it.
Change-Id: Ieb24ea04d4328971ada87bf39b7a0b1c2329e45c
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/81660
Kokoro: Kokoro <noreply+kokoro@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>