memstick: make enable_dma less generic in r592

Fixes this build error:

  drivers/memstick/host/r592.c:26: error: 'enable_dma' redeclared as different kind of symbol
  arch/powerpc/include/asm/dma.h:189: note: previous definition of 'enable_dma' was here

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Alex Dubov <oakad@yahoo.com>
Acked-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/memstick/host/r592.c

@@ -23,7 +23,7 @@
 #include <linux/swab.h>
 #include "r592.h"
 
-static int enable_dma = 1;
+static int r592_enable_dma = 1;
 static int debug;
 
 static const char *tpc_names[] = {
@@ -267,7 +267,7 @@ static void r592_stop_dma(struct r592_device *dev, int error)
 /* Test if hardware supports DMA */
 static void r592_check_dma(struct r592_device *dev)
 {
-	dev->dma_capable = enable_dma &&
+	dev->dma_capable = r592_enable_dma &&
 		(r592_read_reg(dev, R592_FIFO_DMA_SETTINGS) &
 			R592_FIFO_DMA_SETTINGS_CAP);
 }
@@ -898,7 +898,7 @@ static void __exit r592_module_exit(void)
 module_init(r592_module_init);
 module_exit(r592_module_exit);
 
-module_param(enable_dma, bool, S_IRUGO);
+module_param_named(enable_dma, r592_enable_dma, bool, S_IRUGO);
 MODULE_PARM_DESC(enable_dma, "Enable usage of the DMA (default)");
 module_param(debug, int, S_IRUGO | S_IWUSR);
 MODULE_PARM_DESC(debug, "Debug level (0-3)");