patch 9.0.1913: if_python: undefined behaviour for function pointers

Problem:  if_python: undefined behaviour for function pointers
Solution: Fix if_python undefined behavior for function pointer casts

Identified by clang 17 UBSAN (see #12745). Make sure to cast function
pointers with the same signature only.

closes: #13122

Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
diff --git a/src/if_python.c b/src/if_python.c
index 863e931..c6b14fe 100644
--- a/src/if_python.c
+++ b/src/if_python.c
@@ -1103,7 +1103,7 @@
 	    p_pyx = 2;
 
 	DoPyCommand(script == NULL ? (char *) eap->arg : (char *) script,
-		(rangeinitializer) init_range_cmd,
+		init_range_cmd,
 		(runner) run_cmd,
 		(void *) eap);
     }
@@ -1154,7 +1154,7 @@
 
     // Execute the file
     DoPyCommand(buffer,
-	    (rangeinitializer) init_range_cmd,
+	    init_range_cmd,
 	    (runner) run_cmd,
 	    (void *) eap);
 }
@@ -1166,7 +1166,7 @@
 	p_pyx = 2;
 
     DoPyCommand((char *)eap->arg,
-	    (rangeinitializer) init_range_cmd,
+	    init_range_cmd,
 	    (runner)run_do,
 	    (void *)eap);
 }
@@ -1524,7 +1524,7 @@
 do_pyeval(char_u *str, typval_T *rettv)
 {
     DoPyCommand((char *) str,
-	    (rangeinitializer) init_range_eval,
+	    init_range_eval,
 	    (runner) run_eval,
 	    (void *) rettv);
     if (rettv->v_type == VAR_UNKNOWN)