mmc: core: Don't use extern declarations of public mmc functions

Using extern when declaring functions in the public header, core.h, is
redundant. Let's just remove the use of it.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Shawn Lin <shawn.lin@rock-chips.com>

include/linux/mmc/core.h

@@ -158,13 +158,14 @@ struct mmc_request {
 struct mmc_card;
 struct mmc_async_req;
 
-extern struct mmc_async_req *mmc_start_req(struct mmc_host *,
-					   struct mmc_async_req *,
-					   enum mmc_blk_status *);
-extern void mmc_wait_for_req(struct mmc_host *, struct mmc_request *);
-extern int mmc_wait_for_cmd(struct mmc_host *, struct mmc_command *, int);
-
-extern int mmc_hw_reset(struct mmc_host *host);
-extern void mmc_set_data_timeout(struct mmc_data *, const struct mmc_card *);
+struct mmc_async_req *mmc_start_req(struct mmc_host *host,
+				struct mmc_async_req *areq,
+				enum mmc_blk_status *ret_stat);
+void mmc_wait_for_req(struct mmc_host *host, struct mmc_request *mrq);
+int mmc_wait_for_cmd(struct mmc_host *host, struct mmc_command *cmd,
+		int retries);
+
+int mmc_hw_reset(struct mmc_host *host);
+void mmc_set_data_timeout(struct mmc_data *data, const struct mmc_card *card);
 
 #endif /* LINUX_MMC_CORE_H */