Fix list of LTS braches in CONTRIBUTING.md, and back link from BRANCHES.md
Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index b3a9547..dcaa360 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -52,8 +52,7 @@
The list of maintained branches can be found in the [Current Branches section
of BRANCHES.md](BRANCHES.md#current-branches).
-Currently maintained LTS branches are:
-1. [mbedtls-2.7](https://github.com/ARMmbed/mbedtls/tree/mbedtls-2.7)
+The only currently maintained LTS branch is:
1. [mbedtls-2.16](https://github.com/ARMmbed/mbedtls/tree/mbedtls-2.16)