fix: health check path for device when iommuFD is supported

[rajatchopra]

When IommuFD is supported, the wrong paths were put into the fsNotifier. Fixed.

Before:

2026/03/11 19:06:27 iommufd supported: true
2026/03/11 19:06:27 Device map: map[2321:[0 1]]
2026/03/11 19:06:27 Registering device plugin "pgpu" with 2 device(s)
2026/03/11 19:06:27 Devicename pgpu
2026/03/11 19:06:27 pgpu Device plugin server ready
2026/03/11 19:06:27 healthCheck(pgpu): invoked
2026/03/11 19:06:27  Adding Watcher to Path : /dev/vfio/devices/0
2026/03/11 19:06:27 healthCheck(pgpu): Unable to add device path to fsnotify watcher: no such file or directory

After:

2026/03/11 19:05:56 iommufd supported: true
2026/03/11 19:05:56 Device map: map[2321:[0 1]]
2026/03/11 19:05:56 Registering device plugin "pgpu" with 2 device(s)
2026/03/11 19:05:56 Devicename pgpu
2026/03/11 19:05:56 pgpu Device plugin server ready
2026/03/11 19:05:56 healthCheck(pgpu): invoked
2026/03/11 19:05:56  Adding Watcher to Path : /dev/vfio/devices/vfio0
2026/03/11 19:05:56  Adding Watcher to Path : /dev/vfio/devices/vfio1

[jojimt]

lgtm