* stdint.h: Fix gcc c99-stdint-1 testcase (define UINT8_MAX and
	UINT16_MAX without the trailing 'U')

git-svn-id: svn+ssh://svn.code.sf.net/p/mingw-w64/code/trunk@1178 4407c894-4637-0410-b4f5-ada5f102cad1