VFS: Prepare atomic_open() for dentry_create()

VFS: Prepare atomic_open() for dentry_create()

The next patch allows dentry_create() to call atomic_open(), but it does
not have fabricated nameidata.  Let atomic_open() take a path instead.

Since atomic_open() currently takes a nameidata of which it only uses the
path and the flags, and flags are only used to update open_flags, then the
flag update can happen before calling atomic_open(). Then, only the path
needs be passed to atomic_open() rather than the whole nameidata.  This
makes it easier for dentry_create() To call atomic_open().

Signed-off-by: Benjamin Coddington <bcodding@hammerspace.com>
Link: https://patch.msgid.link/e8c1d2ca28de4a972d37e78599502108148fe17d.1764259052.git.bcodding@hammerspace.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>