From patchwork series 497055

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=497055

Author: Fox Snowpatch

drivers/char/nvram.c

@@ -53,7 +53,7 @@
 #include <asm/nvram.h>
 #endif
 
-static DEFINE_MUTEX(nvram_mutex);
+static __maybe_unused DEFINE_MUTEX(nvram_mutex);
 static DEFINE_SPINLOCK(nvram_state_lock);
 static int nvram_open_cnt;	/* #times opened */
 static int nvram_open_mode;	/* special open modes */