Revert MAIL(name) macro

include/mail.h

@@ -21,7 +21,6 @@
 #define FIRST_MAIL_IDX ITEM_ORANGE_MAIL
 
 #define ITEM_TO_MAIL(itemId) (itemId - FIRST_MAIL_IDX)
-#define MAIL(name) (ITEM_TO_MAIL(ITEM_##name##_MAIL))
 
 void ReadMail(struct MailStruct * mail, void (*savedCallback)(void), bool8 messageExists);