Where can I find the information about the mapping the Linux Image v2.7b1+ and the u-boot version used in that image? (In the Release Notes for the Apalis TK1 Linux Images are just entries till V2.6.1 Beta 2.)
How can I figure out which u-boot commit is included in a specific Apalis TK1 Linux Image (BSP) version?
You can trace back over the tags applied in https://git.toradex.com/cgit/u-boot-toradex.git/log/?h=2016.11-toradex for specific branches.
If one could read one would notice the following noted towards the top of mentioned release note text file:
==> For newer images find the release details in the Toradex developer article: http://developer.toradex.com/software/linux/linux-software/release-details
Yes, or one could just use the git client consulting its documentation for further help.