MIPS: DEC: use IS_ENABLED()

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/3333/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/dec/prom/memory.c b/arch/mips/dec/prom/memory.c
index e95ff30..8c62316 100644
--- a/arch/mips/dec/prom/memory.c
+++ b/arch/mips/dec/prom/memory.c
@@ -101,7 +101,7 @@
 	 * the first page reserved for the exception handlers.
 	 */
 
-#if defined(CONFIG_DECLANCE) || defined(CONFIG_DECLANCE_MODULE)
+#if IS_ENABLED(CONFIG_DECLANCE)
 	/*
 	 * Leave 128 KB reserved for Lance memory for
 	 * IOASIC DECstations.