mmc: core: Use MMC_UNSAFE_RESUME as default behavior

Invoking system suspend or shutdown without using the Kconfig option
MMC_UNSAFE_RESUME, did trigger an ungraceful power cut of the card.

To improve the situation, change the behavior to always make use of the
available bus_ops callbacks that handles system suspend and shutdown
properly.

By changing the behavior MMC_UNSAFE_RESUME becomes redundant, so lets's
remove it.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Chris Ball <chris@printf.net>
diff --git a/include/linux/mmc/host.h b/include/linux/mmc/host.h
index 99f5709..2a139b2 100644
--- a/include/linux/mmc/host.h
+++ b/include/linux/mmc/host.h
@@ -424,12 +424,9 @@
 
 int mmc_pm_notify(struct notifier_block *notify_block, unsigned long, void *);
 
-/* Module parameter */
-extern bool mmc_assume_removable;
-
 static inline int mmc_card_is_removable(struct mmc_host *host)
 {
-	return !(host->caps & MMC_CAP_NONREMOVABLE) && mmc_assume_removable;
+	return !(host->caps & MMC_CAP_NONREMOVABLE);
 }
 
 static inline int mmc_card_keep_power(struct mmc_host *host)