[MIPS] Kconfig: Fix configuration warning by hardwiring HOTPLUG_CPU to n.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index f588b55..2f2fd19 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -697,6 +697,10 @@
 	bool
 	select ZONE_DMA
 
+config HOTPLUG_CPU
+	bool
+	default n
+
 config I8259
 	bool