Add RPC as a common initialism.
diff --git a/lint.go b/lint.go
index 21e1678..385d96e 100644
--- a/lint.go
+++ b/lint.go
@@ -354,6 +354,7 @@
 	"ID":    true,
 	"IP":    true,
 	"JSON":  true,
+	"RPC":   true,
 	"URL":   true,
 	"XML":   true,
 }