fix avr32 build errors

Commit 7d2be0749a59096a334c94dc48f43294193cb8ed
(atmel-mci: Driver for Atmel on-chip MMC controllers)
causes build errors like:

<-- snip -->

...
CC arch/avr32/boards/atstk1000/atstk1003.o
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/avr32/boards/atstk1000/atstk1003.c: In function 'atstk1003_init':
/home/bunk/linux/kernel-2.6/git/linux-2.6/arch/avr32/boards/atstk1000/atstk1003.c:157: error: too few arguments to function 'at32_add_device_mci'
make[2]: *** [arch/avr32/boards/atstk1000/atstk1003.o] Error 1

<-- snip -->

Reported-by: Adrian Bunk <[e-mail]>
Signed-off-by: Adrian Bunk <[e-mail]>
Signed-off-by: Haavard Skinnemoen <[e-mail]>

arch/avr32/boards/atstk1000/atstk1003.c

···
 	at32_add_device_spi(1, spi1_board_info, ARRAY_SIZE(spi1_board_info));
 #endif
 #ifndef CONFIG_BOARD_ATSTK100X_SW2_CUSTOM
-	at32_add_device_mci(0);
+	at32_add_device_mci(0, NULL);
 #endif
 	at32_add_device_usba(0, NULL);
 #ifndef CONFIG_BOARD_ATSTK100X_SW3_CUSTOM

arch/avr32/boards/atstk1000/atstk1004.c

···
 	at32_add_device_spi(1, spi1_board_info, ARRAY_SIZE(spi1_board_info));
 #endif
 #ifndef CONFIG_BOARD_ATSTK100X_SW2_CUSTOM
-	at32_add_device_mci(0);
+	at32_add_device_mci(0, NULL);
 #endif
 	at32_add_device_lcdc(0, &atstk1000_lcdc_data,
 			     fbmem_start, fbmem_size, 0);