Pull and resolve conflicts by using changes from the origin.

Use:

git pull -X theirs <origin> <branchname>

or directly (if there's already a tracking branch associated to the local branch):

git pull -X theirs

The -X theirs specifies that the merge strategy in case of conflicts should be to use the changes coming from origin.

Also, if you want to avoid merge commits combine the former with --rebase. Like:

git pull -X theirs --rebase