Fix warnings for ilog (see below) gcc 4.1, and testsuite fixes.

Fix warnings for ilog (see below) gcc 4.1, and testsuite fixes.
(1) Include ilog.h header first (checks that it doesn't need anything else)
(2) Include ilog.c (only api tests don't need this).

Here are the warnings with gcc 4.1:
Running gcc -O3 -Wall -Wundef -Wstrict-prototypes -Wold-style-definition -Wmissing-prototypes
-Wmissing-declarations -Werror -Iccan/ -I.  -o ccan/ilog/test/run ccan/ilog/test/run.c  ccan/tap/tap.o
In file included from ccan/ilog/test/run.c:2:
ccan/ilog/ilog.h:27:10: error: "LLONG_MAX" is not defined
cc1: warnings being treated as errors
ccan/ilog/test/run.c: In function ‘main’:
ccan/ilog/test/run.c:36: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:55: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:55: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:55: warning: suggest brackets around + or - in operand of &
ccan/ilog/test/run.c:63: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:85: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:85: warning: suggest brackets around + or - inside shift
ccan/ilog/test/run.c:85: warning: suggest brackets around + or - in operand of &