alpha: enable ARCH_DMA_ADDR_T_64BIT

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Matt Turner <mattst88@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/alpha/Kconfig b/arch/alpha/Kconfig
index d04ccd7..28f93a6 100644
--- a/arch/alpha/Kconfig
+++ b/arch/alpha/Kconfig
@@ -55,6 +55,9 @@
 	bool
 	default y
 
+config ARCH_DMA_ADDR_T_64BIT
+	def_bool y
+
 config NEED_DMA_MAP_STATE
        def_bool y