core: Remove FLOATING_DISK_NOT_SUPPORTED

Removed all entries for the key
ACTION_TYPE_FAILED_FLOATING_DISK_NOT_SUPPORTED from the various
AppErrors*.properties, AppErrors.java and VdcBllMessages.java files, as
it is no longer used and has no references in the code.

Change-Id: Id32ee34c4e88b9443218c772d17a2d2ab1e77add
Signed-off-by: Allon Mureinik <amureini@redhat.com>