linux: Update size when telemetry controller initiated data is unavailable

Fix to update size for telemetry log page when telemetry controller
initiated data is unavailable.

Author: akhilesh-rn-wdc

src/nvme/linux.c

@@ -205,6 +205,7 @@ static int nvme_get_telemetry_log(int fd, bool create, bool ctrl, bool rae,
 	telem = log;
 	if (ctrl && !telem->ctrlavail) {
 		*buf = log;
+		*size = xfer;
 		return 0;
 	}