AC_CHECK_TYPE search locations

[Tomas Berndtsson]

AC_CHECK_TYPE only looks in some header files for the type. But, for
other types, there is no way to specify what header file(s) to look
in. For example, the new ISO C 9X standard have uint16_t in stdint.h,
included in inttypes.h but not in sys/types.h. Thus, AC_CHECK_TYPE
cannot find it.


Tomas