When calling debugfs functions, there is no need to ever check the return
value.  The function can work or not, but the code logic should never do
something different based on this.

Cc: Satish Kharat <satishkh@cisco.com>
Cc: Sesidhar Baddela <sebaddel@cisco.com>
Cc: Karan Tilak Kumar <kartilak@cisco.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: NSatish Kharat <satishkh@cisco.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>