mmc: sdhci: Remove unneeded forward declaration of sdhci_finish_data()

sdhci_finish_data() is defined before it is referenced, so forward
declaration is not necessary.
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/20200412090349.1607-4-adrian.hunter@intel.comSigned-off-by: Ulf Hansson <ulf.hansson@linaro.org>

drivers/mmc/host/sdhci.c

@@ -48,8 +48,6 @@
 static unsigned int debug_quirks = 0;
 static unsigned int debug_quirks2;
 
-static void sdhci_finish_data(struct sdhci_host *);
-
 static void sdhci_enable_preset_value(struct sdhci_host *host, bool enable);
 
 static void sdhci_send_command(struct sdhci_host *host, struct mmc_command *cmd);