mmc: mmci: Don't share un-implemented DMA functions

Some of the DMA functions are shared via mmci.h, however they are not
implemented unless CONFIG_DMA_ENGINE is set. Therefore, add that constraint
to the header file as well.
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>

drivers/mmc/host/mmci.h

@@ -429,6 +429,7 @@ struct mmci_host {
 void mmci_write_clkreg(struct mmci_host *host, u32 clk);
 void mmci_write_pwrreg(struct mmci_host *host, u32 pwr);
 
+#ifdef CONFIG_DMA_ENGINE
 int mmci_dmae_prep_data(struct mmci_host *host, struct mmc_data *data,
 			bool next);
 void mmci_dmae_unprep_data(struct mmci_host *host, struct mmc_data *data,
@@ -439,3 +440,4 @@ void mmci_dmae_release(struct mmci_host *host);
 int mmci_dmae_start(struct mmci_host *host, unsigned int *datactrl);
 void mmci_dmae_finalize(struct mmci_host *host, struct mmc_data *data);
 void mmci_dmae_error(struct mmci_host *host);
+#endif