CallstackIsntr: Fix callback types

c575951 incorrectly
change the callback types without changing how they were registered.

Author: Andrew Fasano

panda/plugins/callstack_instr/callstack_instr.cpp

@@ -594,9 +594,9 @@ bool init_plugin(void *self) {
     pcb.after_block_translate = after_block_translate;
     panda_register_callback(self, PANDA_CB_AFTER_BLOCK_TRANSLATE, pcb);
     pcb.end_block_exec = end_block_exec;
-    panda_register_callback(self, PANDA_CB_AFTER_BLOCK_EXEC, pcb);
+    panda_register_callback(self, PANDA_CB_END_BLOCK_EXEC, pcb);
     pcb.start_block_exec = start_block_exec;
-    panda_register_callback(self, PANDA_CB_BEFORE_BLOCK_EXEC, pcb);
+    panda_register_callback(self, PANDA_CB_START_BLOCK_EXEC, pcb);
 
     bool setup_ok = true;