mmc: core: prepend 0x to pre_eol_info entry in sysfs

The sysfs entry "pre_eol_info" was missing the 0x prefix to identify it
as hex formatted.

Fixes: 46bc5c408e ("mmc: core: Export device lifetime information through sysfs")
Signed-off-by: Bastian Stender <bst@pengutronix.de>
Cc: <stable@vger.kernel.org> # v4.11+
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/mmc.c

@@ -781,7 +781,7 @@ MMC_DEV_ATTR(name, "%s\n", card->cid.prod_name);
 MMC_DEV_ATTR(oemid, "0x%04x\n", card->cid.oemid);
 MMC_DEV_ATTR(prv, "0x%x\n", card->cid.prv);
 MMC_DEV_ATTR(rev, "0x%x\n", card->ext_csd.rev);
-MMC_DEV_ATTR(pre_eol_info, "%02x\n", card->ext_csd.pre_eol_info);
+MMC_DEV_ATTR(pre_eol_info, "0x%02x\n", card->ext_csd.pre_eol_info);
 MMC_DEV_ATTR(life_time, "0x%02x 0x%02x\n",
 	card->ext_csd.device_life_time_est_typ_a,
 	card->ext_csd.device_life_time_est_typ_b);