Can anyone tell us a simple way to check?
Intel has on their website info on the processors.
For example, for yours (i7-4700mq) you would look at:
Or you can look for all products that were "formerly haswell":
how to apply the "disable the broken feature" fix - without installing windows
I would do some searches for updating BIOS from linux - ex:
Or doing a microcode update:
Until there is a chip for sale that really supports TSX I wouldn't expect anyone to be distributing software that uses it. So I wouldn't be too worried about it yet.