scsi: esas2r: use ktime_get_real_seconds()

do_gettimeofday() is deprecated because of the y2038 overflow.  Here, we
use the result to pass into a 32-bit field in the firmware, which still
risks an overflow, but if the firmware is written to expect unsigned
values, it can at least last until y2106, and there is not much we can
do about it.

This changes do_gettimeofday() to ktime_get_real_seconds(), which at
least simplifies the code a bit, and avoids the deprecated
interface. I'm adding a comment about the overflow to document what
happens.
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/esas2r/esas2r_init.c

@@ -1202,8 +1202,6 @@ static bool esas2r_format_init_msg(struct esas2r_adapter *a,
 	case ESAS2R_INIT_MSG_START:
 	case ESAS2R_INIT_MSG_REINIT:
 	{
-		struct timeval now;
-		do_gettimeofday(&now);
 		esas2r_hdebug("CFG init");
 		esas2r_build_cfg_req(a,
 				     rq,
@@ -1212,7 +1210,8 @@ static bool esas2r_format_init_msg(struct esas2r_adapter *a,
 				     NULL);
 		ci = (struct atto_vda_cfg_init *)&rq->vrq->cfg.data.init;
 		ci->sgl_page_size = cpu_to_le32(sgl_page_size);
-		ci->epoch_time = cpu_to_le32(now.tv_sec);
+		/* firmware interface overflows in y2106 */
+		ci->epoch_time = cpu_to_le32(ktime_get_real_seconds());
 		rq->flags |= RF_FAILURE_OK;
 		a->init_msg = ESAS2R_INIT_MSG_INIT;
 		break;