webadmin: Fix typo for QoS

Fixed the "Write IOps" column from "Read IOps" -> "Write IOps".

Change-Id: Ic65a15815cc276cd3ec9d0290946a97813c7a434
Bug-Url: https://bugzilla.redhat.com/1139731
Signed-off-by: Tomer Saban <tsaban@redhat.com>