It seems to me like the particular patch is kind of overly subtle. It looks to me like the option doesn't remove the kernel's ability to create such filenames (using the patented technique), but rather just makes the kernel return an error instead of actually deciding to create such a filename. I can't really see a point to such a patch; sure, it makes it impossible to prove that your device violates the patent by demonstrating that it actually creates such files, but with the code that would do it in the source, compiled, and installed, and just unreachable, I think it's unlikely that this detail would affect whether a patent suit could get filed and not get dismissed. And, since everybody seems to agree that, if someone were willing and able to get to a final judgment, the patents wouldn't hold up, there's no point in also not infringing them for a subtle reason.
What I don't understand is why the option isn't there to drop the code that interacts with the long filename content entirely; it seems like it should be easy to make Linux treat these files like DOS did, where files seem to have odd short names (but are otherwise normal), and the hidden files are left alone. I can't think of any device that doesn't need to create files with arbitrary names but does care about the names of existing files with arbitrary names (MP3 players often want to use files that do have arbitrary names, but they identify the files with metadata from the files themselves, not from the filesystem).
I think this would also be cleaner in the code, and make it easy enough to show that the source you compiled to put on your device didn't contain any code that infringes the patent.