sunrpc: eliminate RPC_DEBUG

It's always set to whatever CONFIG_SUNRPC_DEBUG is, so just use that.

Signed-off-by: Jeff Layton <jlayton@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c
index 53ed8d3..dace13d 100644
--- a/net/sunrpc/auth_gss/auth_gss.c
+++ b/net/sunrpc/auth_gss/auth_gss.c
@@ -66,7 +66,7 @@
 #define GSS_KEY_EXPIRE_TIMEO 240
 static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO;
 
-#ifdef RPC_DEBUG
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
 # define RPCDBG_FACILITY	RPCDBG_AUTH
 #endif