m68k: Use IS_ENABLED() instead of checking for built-in or module

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
diff --git a/arch/m68k/mac/config.c b/arch/m68k/mac/config.c
index 2f33a33..e468953 100644
--- a/arch/m68k/mac/config.c
+++ b/arch/m68k/mac/config.c
@@ -162,7 +162,7 @@
 	mach_halt = mac_poweroff;
 	mach_power_off = mac_poweroff;
 	mach_max_dma_address = 0xffffffff;
-#if defined(CONFIG_INPUT_M68K_BEEP) || defined(CONFIG_INPUT_M68K_BEEP_MODULE)
+#if IS_ENABLED(CONFIG_INPUT_M68K_BEEP)
 	mach_beep = mac_mksound;
 #endif