mmc_spi.h should include linux/interrupts.h

Since mmc_spi.h uses irqreturn_t type, it should include appropriate header, otherwise build will break if users didn't include it (some of them do not use interrupts).

---
 include/linux/spi/mmc_spi.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

index e9bbe3e..d5ca78b 100644
@@ -1,6 +1,8 @@
 #ifndef __LINUX_SPI_MMC_SPI_H
 #define __LINUX_SPI_MMC_SPI_H
 
+#include <linux/interrupt.h>
+
 struct device;
 struct mmc_host;
 

1.5.5.1