MMC: tmio_mmc.h: fix build problem

drivers/mmc/host/tmio_mmc.h: In function 'tmio_mmc_kmap_atomic':
drivers/mmc/host/tmio_mmc.h:147: error: implicit declaration of function 'kmap_atomic'
drivers/mmc/host/tmio_mmc.h:147: error: 'KM_BIO_SRC_IRQ' undeclared (first use in this function)
drivers/mmc/host/tmio_mmc.h: In function 'tmio_mmc_kunmap_atomic':
drivers/mmc/host/tmio_mmc.h:153: error: implicit declaration of function 'kunmap_atomic'
drivers/mmc/host/tmio_mmc.h:153: error: 'KM_BIO_SRC_IRQ' undeclared (first use in this function)

Signed-off-by: Alexander Beregalov <a.beregalov@gmail.com>
Signed-off-by: Pierre Ossman <drzeus@drzeus.cx>

drivers/mmc/host/tmio_mmc.h

@@ -8,6 +8,9 @@
  * published by the Free Software Foundation.
  *
  */
+
+#include <linux/highmem.h>
+
 #define CNF_CMD     0x04
 #define CNF_CTL_BASE   0x10
 #define CNF_INT_PIN  0x3d