scsi: qedf: remove memset/memcpy to nfunc and use func instead

Currently the qedf_dbg_* family of functions can overrun the end of the
source string if it is less than the destination buffer length because of
the use of a fixed sized memcpy. Remove the memset/memcpy calls to nfunc
and just use func instead as it is always a null terminated string.

Addresses-Coverity: ("Out-of-bounds access")
Fixes: 61d8658b ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Acked-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>