Assume sized integral types are available

In globalDefinitions_gcc.hpp we have conditionalized includes of <inttypes.h> and declarations of various sized types. None of that conditionalization is needed any more. Sized types via <stdint.h> (or <cstdint>) and their format specifiers via <inttypes.h> (or <cinttypes>) and 64 bit integral types are part of the C++ standard we are using for HotSpot.

globalDefinitions_gcc.hpp should be changed to just unconditionally include stdint.h and inttypes.h.