staging: mt7621-mmc: Remove unused global dma_size

The global variable dma_size was previously used to select DMA or
non-DMA transfer mode based on the size of the data that should be
transferred. This option was removed preivously, so the variable is not
used any more and can be removed.
Signed-off-by: Christian Lütke-Stetzkamp <christian@lkamp.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/mt7621-mmc/dbg.c

@@ -58,14 +58,6 @@ unsigned int sd_debug_zone[4] = {
 	0
 };
 
-/* mode select */
-u32 dma_size[4] = {
-	512,
-	512,
-	512,
-	512
-};
-
 #if defined(MT6575_SD_DEBUG)
 /* for driver profile */
 #define TICKS_ONE_MS  (13000)

drivers/staging/mt7621-mmc/dbg.h

@@ -79,8 +79,6 @@ enum msdc_mode {
 	MODE_SIZE_DEP = 2,
 };
 
-extern u32 dma_size[4];
-
 /* Debug message event */
 #define DBG_EVT_NONE        (0)       /* No event */
 #define DBG_EVT_DMA         (1 << 0)  /* DMA related event */