_content/doc/go1.26: remove unnecessary footnotes

The links are already included above inlined. The footnotes are
not referenced anywhere. Remove.

For golang/go#75005.

Change-Id: I8cf502d24bd6e2ee17fa91fe11b3ed18ce58f71b
Reviewed-on: https://go-review.googlesource.com/c/website/+/738560
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Carlos Amedee <carlos@golang.org>

_content/doc/go1.26.md

diff --git a/_content/doc/go1.26.md b/_content/doc/go1.26.md
index 5b6e48e..c1fb0ae 100644
--- a/_content/doc/go1.26.md
+++ b/_content/doc/go1.26.md
@@ -743,6 +743,3 @@
 heap memory in much smaller increments, leading to significantly
 reduced memory usage for applications with heaps less than around
 16 MiB in size.
-
-[laelf-20250521]: https://github.com/loongson/la-abi-specs/blob/v2.40/laelf.adoc
-[rfc 9180]: https://rfc-editor.org/rfc/rfc9180.html