Move PRIu64 Windows workaround to compat.h

So that we can use it from several files.

PR #2814 <https://github.com/Genymobile/scrcpy/pull/2814>

app/src/compat.h

@@ -6,6 +6,12 @@
 #include <libavformat/version.h>
 #include <SDL2/SDL_version.h>
 
+#ifndef __WIN32
+# define PRIu64_ PRIu64
+#else
+# define PRIu64_ "I64u"  // Windows...
+#endif
+
 // In ffmpeg/doc/APIchanges:
 // 2018-02-06 - 0694d87024 - lavf 58.9.100 - avformat.h
 //   Deprecate use of av_register_input_format(), av_register_output_format(),

app/src/control_msg.c

@@ -171,11 +171,6 @@ control_msg_log(const struct control_msg *msg) {
                          (long) msg->inject_touch_event.buttons);
             } else {
                 // numeric pointer id
-#ifndef __WIN32
-# define PRIu64_ PRIu64
-#else
-# define PRIu64_ "I64u"  // Windows...
-#endif
                 LOG_CMSG("touch [id=%" PRIu64_ "] %-4s position=%" PRIi32 ",%"
                              PRIi32 " pressure=%g buttons=%06lx",
                          id,