you could do:
git checkout <remote_branch> <paths>
where <paths>
is the files that you actually want. this is easiest if the files you want are in separate directories to the files you don't, as you can use wildcards.
alternatively, try:
git pull --squash
this may be a bit manual, as you then have to go and delete the files you don't want before committing, but it is also the only way to do it if the files you don't want have been added as part of the same commit that changed files you do want.
the (fairly major) downside is that you lose the commit history of the remote branch.