bpo-30604: Fix __PyCodeExtraState_Get() prototype (#2152)

Replace __PyCodeExtraState_Get() with __PyCodeExtraState_Get(void) to
fix the following GCC warning:

./Include/pystate.h:63:1: warning: function declaration isn't a prototype [-Wstrict-prototypes]
 __PyCodeExtraState* __PyCodeExtraState_Get();

1 files changed, 2 insertions, 2 deletions

diff --git a/Python/pystate.c b/Python/pystate.c
index 92d08c4..65f9b7e 100644
--- a/Python/pystate.c
+++ b/Python/pystate.c
@@ -571,8 +571,8 @@ PyThreadState_Swap(PyThreadState *newts)
     return oldts;
 }
 
-__PyCodeExtraState* 
-__PyCodeExtraState_Get() {
+__PyCodeExtraState*
+__PyCodeExtraState_Get(void) {
     PyInterpreterState* interp = PyThreadState_Get()->interp;
 
     HEAD_LOCK();