crypto: cavium/nitrox - Fix build with !CONFIG_DEBUG_FS

Fixes: cf718eaa8f ("crypto: cavium/nitrox - Enabled Mailbox support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/cavium/nitrox/nitrox_debugfs.h

@@ -13,9 +13,8 @@ static inline int nitrox_debugfs_init(struct nitrox_device *ndev)
 	return 0;
 }
 
-static inline int nitrox_sriov_debugfs_init(struct nitrox_device *ndev)
+static inline void nitrox_debugfs_exit(struct nitrox_device *ndev)
 {
-	return 0;
 }
 #endif /* !CONFIG_DEBUG_FS */