mmc: sdhci: mmc_rescan: reduce verbosity

mmc_rescan() includes a pr_info which prints 4 lines each second for
hosts configured with MMC_CAP_NEEDS_POLL. This patch enables the message
only if CONFIG_MMC_DEBUG is selected. Tested on i.MX51's sdhci-esdhc.

Signed-off-by: Eric Bénard <eric@eukrea.com>
Acked-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Hein Tibosch <hein_tibosch@yahoo.es>
Signed-off-by: Chris Ball <cjb@laptop.org>

drivers/mmc/core/core.c

@@ -1452,9 +1452,10 @@ void mmc_rescan(struct work_struct *work)
 			mmc_release_host(host);
 			goto out;
 		}
+#ifdef CONFIG_MMC_DEBUG
 		pr_info("%s: %s: trying to init card at %u Hz\n",
 			mmc_hostname(host), __func__, host->f_init);
-
+#endif
 		mmc_power_up(host);
 		sdio_reset(host);
 		mmc_go_idle(host);