jimtcl: update to 0.76 release version

It makes sense to use the latest released version to ensure
compatibility.

Change-Id: I0957f927d825fa6fb6a1594ca17bcca46ee6c1a6
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Reviewed-on: http://openocd.zylin.com/2522
Tested-by: jenkins
Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>

diff --git a/jimtcl b/jimtcl
index 72bbd6c5a327bdc1d5ea8cb12502640860b1fc44..51f65c6d38fbf86e1f0b036ad336761fd2ab7fa0 160000 (submodule)
--- a/jimtcl
+++ b/jimtcl
@@ -1 +1 @@
-Subproject commit 72bbd6c5a327bdc1d5ea8cb12502640860b1fc44
+Subproject commit 51f65c6d38fbf86e1f0b036ad336761fd2ab7fa0