[LU-2762] rhel: use upstream ext4_kvzalloc

• Type: Improvement
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.5.0
• Labels: patch
• Assignee: Bob Glossman (Inactive)
• Reporter: Jeff Mahoney

Description

Upstream commits f18a5f21 (v3.1) and 9933fc0a (v3.1) added and used
ext4_kvzalloc in the same matter the previous ldiskfs patches did but without open-coding it. We should use that instead of the open-coded versions.