RAIDZ expansion incorrectly reports flag not enabled with some attach options

[solidsnake1298]

System information

Distribution Name | Ubuntu
Distribution Version | 24.04.2
Kernel Version | 6.11.0-17-generic
Architecture | AMD64
OpenZFS Version | 2.3.0+release-noble4

Describe the problem you're observing

When attaching a new disk to an existing RAIDZ1 for RAIDZ expansion while including -s and -w options incorrectly reports that the raidz_expansion feature flag is not enabled.

Describe how to reproduce the problem

Add a disk to an existing vdev with the following command.

zpool attach -fsw <pool> <raidzN-p> <new disk identifier>

Including the -s and -w options result in this message.

cannot attach wwn-0x5000cca0d2c46644 to raidz1-0: raidz_expansion feature must be enabled in order to attach a device to raidz

Removing the -s and -w options results in a successful attach and RAIDZ expansion.