[MIPS] Kconfig: Enable 64BIT_PHYS_ADDR only through select.

The user should not have to have any clue about this setting.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/au1000/Kconfig b/arch/mips/au1000/Kconfig
index abea880..29c95d9 100644
--- a/arch/mips/au1000/Kconfig
+++ b/arch/mips/au1000/Kconfig
@@ -136,6 +136,7 @@
 
 config SOC_AU1X00
 	bool
+	select 64BIT_PHYS_ADDR
 	select SYS_HAS_CPU_MIPS32_R1
 	select SYS_SUPPORTS_32BIT_KERNEL
 	select SYS_SUPPORTS_APM_EMULATION