kernel: include inttypes.h to get access to PRI defines in most spots

We need to move using the PRI* defines to use newlib as the default libc
as different arch's define various base types like {u}int32_t
differently.  To deal with that in a consistent manor we need access to
the defines in most spots for print{f,k} or logging functions.

Change-Id: Ic1fbef75cbaee211803d9aaf506056e5e31e73f3
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>