builtin: add a `[has_globals]` tag for all the .v files, with global declarations in them

vlib/builtin/builtin.c.v

@@ -1,3 +1,4 @@
+[has_globals]
 module builtin
 
 type FnExitCb = fn ()

vlib/builtin/builtin.v

@@ -1,6 +1,7 @@
 // Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
+[has_globals]
 module builtin
 
 // isnil returns true if an object is nil (only for C objects).

vlib/builtin/builtin_windows.c.v

@@ -1,6 +1,7 @@
 // Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
 // Use of this source code is governed by an MIT license
 // that can be found in the LICENSE file.
+[has_globals]
 module builtin
 
 // dbghelp.h is already included in cheaders.v
@@ -66,9 +67,7 @@ const (
 )
 
 // g_original_codepage - used to restore the original windows console code page when exiting
-__global (
-	g_original_codepage = u32(0)
-)
+__global g_original_codepage = u32(0)
 
 // utf8 to stdout needs C.SetConsoleOutputCP(C.CP_UTF8)
 fn C.GetConsoleOutputCP() u32

vlib/builtin/prealloc.c.v

@@ -1,3 +1,4 @@
+[has_globals]
 module builtin
 
 // With -prealloc, V calls libc's malloc to get chunks, each at least 16MB