ccan/list: remove conflicting LIST_HEAD definition
ccan/list: remove conflicting LIST_HEAD definition

LIST_HEAD is also declared in sys/queue.h, which is needed for libevent.

Signed-off-by: David Disseldorp <589a549dc9f982d9f46aeeb82a09ab6d87ccf1d8@suse.de>

ddiss/elasto,ddiss/elasto