powerpc: enable ARCH_DMA_ADDR_T_64BIT with ARCH_PHYS_ADDR_T_64BIT

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/Kconfig

@@ -20,6 +20,9 @@ config WORD_SIZE
 config ARCH_PHYS_ADDR_T_64BIT
        def_bool PPC64 || PHYS_64BIT
 
+config ARCH_DMA_ADDR_T_64BIT
+	def_bool ARCH_PHYS_ADDR_T_64BIT
+
 config MMU
 	bool
 	default y