main-func: Reduce transitive includes

Let's move some logic from _DEFINE_MAIN_FUNCTION() and other places
in main-func.h into functions that we implement in main-func.c to
allow moving some included headers from the header to the .c file.

src/cryptsetup/cryptsetup.c

@@ -13,6 +13,7 @@
 #include "sd-messages.h"
 
 #include "alloc-util.h"
+#include "argv-util.h"
 #include "ask-password-api.h"
 #include "build.h"
 #include "cryptsetup-fido2.h"