global: remove unnecessary includes from headers.

Each header should only include the other headers it needs to compile;
`devtools/reduce-includes.sh */*.h` does this.  The C files then need
additional includes if they don't compile.

And remove the entirely useless wire/onion_wire.h, which only serves to include wire/onion_wiregen.h.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

cli/lightning-cli.c

@@ -17,6 +17,7 @@
 #include <common/utils.h>
 #include <common/version.h>
 #include <libgen.h>
+#include <stdio.h>
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <sys/wait.h>