scsi: be2iscsi: mark symbols static where possible

We get 6 warnings when building kernel with W=1:
drivers/scsi/be2iscsi/be_main.c:65:1: warning: no previous prototype for 'beiscsi_log_enable_disp' [-Wmissing-prototypes]
drivers/scsi/be2iscsi/be_main.c:78:1: warning: no previous prototype for 'beiscsi_log_enable_change' [-Wmissing-prototypes]
drivers/scsi/be2iscsi/be_main.c:97:1: warning: no previous prototype for 'beiscsi_log_enable_store' [-Wmissing-prototypes]
drivers/scsi/be2iscsi/be_main.c:116:1: warning: no previous prototype for 'beiscsi_log_enable_init' [-Wmissing-prototypes]
drivers/scsi/be2iscsi/be_main.c:4587:5: warning: no previous prototype for 'beiscsi_iotask_v2' [-Wmissing-prototypes]
drivers/scsi/be2iscsi/be_main.c:4976:6: warning: no previous prototype for 'beiscsi_hba_attrs_init' [-Wmissing-prototypes]

In fact, these functions are only used in the file in which they are
declared and don't need a declaration, but can be made static. So this
patch marks these functions with 'static'.

Signed-off-by: Baoyou Xie <baoyou.xie@linaro.org>
Reviewed-by: Jitendra Bhivare <Jitendra.bhivare@broadcom>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>