rxrpc: Adjust some whitespace and comments

Remove some excess whitespace, insert some missing spaces and adjust a
couple of comments.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/net/rxrpc/ar-security.c b/net/rxrpc/ar-security.c
index e2f4c49..ceff639 100644
--- a/net/rxrpc/ar-security.c
+++ b/net/rxrpc/ar-security.c
@@ -167,7 +167,7 @@
 	struct rxrpc_sock *rx;
 	struct key *key;
 	key_ref_t kref;
-	char kdesc[5+1+3+1];
+	char kdesc[5 + 1 + 3 + 1];
 
 	_enter("");