[SCSI] qla4xxx: Silence gcc warning

Fix followig gcc warning:-
drivers/scsi/qla4xxx/ql4_os.c: In function ‘qla4xxx_sysfs_ddb_get_param’:
drivers/scsi/qla4xxx/ql4_os.c:6279:
warning: comparison is always true due to limited range of data type
drivers/scsi/qla4xxx/ql4_os.c:6290:
warning: comparison is always true due to limited range of data type
drivers/scsi/qla4xxx/ql4_os.c: In function ‘qla4xxx_sysfs_ddb_delete’:
drivers/scsi/qla4xxx/ql4_os.c:6593:
warning: ‘ddb_size’ may be used uninitialized in this function

Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>