Merge branch 'js/mingw-remove-unused-extern-decl' into maint-2.45

An unused extern declaration for mingw has been removed to prevent
it from causing build failure.

* js/mingw-remove-unused-extern-decl:
  mingw: drop bogus (and unneeded) declaration of `_pgmptr`

compat/mingw.c

@@ -26,7 +26,6 @@ static const int delay[] = { 0, 1, 10, 20, 40 };
 void open_in_gdb(void)
 {
 	static struct child_process cp = CHILD_PROCESS_INIT;
-	extern char *_pgmptr;
 
 	strvec_pushl(&cp.args, "mintty", "gdb", NULL);
 	strvec_pushf(&cp.args, "--pid=%d", getpid());