efs: fix the efs new mount api implementation

[ Upstream commit 51ceeb1a ]

Commit 39a6c668 (efs: convert efs to use the new mount api)
did not include anything from v2 and v3 that were also submitted.
Fix this by bringing in those changes that were proposed in v2 and
v3.

Fixes: 39a6c668 efs: convert efs to use the new mount api.

Signed-off-by: Bill O'Donnell <bodonnel@redhat.com>
Link: https://lore.kernel.org/r/20241014190241.4093825-1-bodonnel@redhat.com


Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>