Prefer inttypes.h to stdint.h.

The former also defines the printf() macros.
Also define __STDC_FORMAT_MACROS before including it to make
the printf() macros more likely to work with C++.
diff --git a/CMakeLists.txt b/CMakeLists.txt
index f8eb16e..b385c4b 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -313,10 +313,11 @@
 
 # fixed size integral types
 
-IF(HAVE_STDINT_H_LIBZIP)
+IF(HAVE_INTTYPES_H_LIBZIP)
+  SET(LIBZIP_TYPES_INCLUDE "#define __STDC_FORMAT_MACROS 1
+#include <inttypes.h>")
+ELSEIF(HAVE_STDINT_H_LIBZIP)
   SET(LIBZIP_TYPES_INCLUDE "#include <stdint.h>")
-ELSEIF(HAVE_INTTYPES_H_LIBZIP)
-  SET(LIBZIP_TYPES_INCLUDE "#include <inttypes.h>")
 ELSEIF(HAVE_SYS_TYPES_H_LIBZIP)
   SET(LIBZIP_TYPES_INCLUDE "#include <sys/types.h>")
 ENDIF()