x11-wm/sawfish: Fix build with -fno-common

Add a patch from upstream to fix the build of x11-wm/sawfish with
-fno-common, which is the default with llvm 11.

MFH:		2020Q3 (implicit, -fno-common fixes, ok by joenum)

x11-wm/sawfish/files/patch-d4364707.c

@@ -0,0 +1,88 @@
+diff --git a/src/flippers.c b/src/flippers.c
+index c18efcf3..1b248e68 100644
+--- src/flippers.c
++++ src/flippers.c
+@@ -22,10 +22,6 @@
+ 
+ static Window edge_left, edge_right, edge_top, edge_bottom;
+ 
+-DEFSYM(left, "left");
+-DEFSYM(right, "right");
+-DEFSYM(top, "top");
+-DEFSYM(bottom, "bottom");
+ DEFSYM(enter_flipper_hook, "enter-flipper-hook");
+ DEFSYM(leave_flipper_hook, "leave-flipper-hook");
+ 
+@@ -155,10 +151,6 @@ flippers_init (void)
+ 
+     rep_pop_structure (tem);
+ 
+-    rep_INTERN (left);
+-    rep_INTERN (right);
+-    rep_INTERN (top);
+-    rep_INTERN (bottom);
+     rep_INTERN_SPECIAL (enter_flipper_hook);
+     rep_INTERN_SPECIAL (leave_flipper_hook);
+     Fset(Qenter_flipper_hook, Qnil);
+diff --git a/src/functions.c b/src/functions.c
+index ff797529..7b191151 100644
+--- src/functions.c
++++ src/functions.c
+@@ -65,7 +65,6 @@ static int xinerama_heads;
+ # endif
+ #endif
+ 
+-DEFSYM(root, "root");
+ DEFSYM(after_restacking_hook, "after-restacking-hook");
+ DEFSYM(position, "position");
+ DEFSYM(spacing, "spacing");
+@@ -1406,7 +1405,6 @@ functions_init (void)
+     rep_ADD_SUBR(Ssend_client_message);
+     rep_pop_structure (tem);
+ 
+-    rep_INTERN(root);
+     rep_INTERN_SPECIAL(after_restacking_hook);
+     Fset(Qafter_restacking_hook, Qnil);
+     rep_INTERN(position);
+diff --git a/src/sawfish_subrs.h b/src/sawfish_subrs.h
+index 8b1e7a2c..e2256249 100644
+--- src/sawfish_subrs.h
++++ src/sawfish_subrs.h
+@@ -79,7 +79,7 @@ extern void (*event_handlers[LASTEvent])(XEvent *ev);
+ extern Time last_event_time;
+ extern XEvent *current_x_event;
+ extern repv Qvisibility_notify_hook, Qdestroy_notify_hook, Qmap_notify_hook,
+-    Qunmap_notify_hook, Qreparent_notify_hook, Qenter_notify_hook,
++    Qunmap_notify_hook, Qreparent_notify_hook, Qenter_notify_hook, Qroot,
+     Qleave_notify_hook, Qfocus_in_hook, Qfocus_out_hook, Qclient_message_hook,
+     Qwindow_moved_hook, Qwindow_resized_hook, Qrandr_change_notify_hook;
+ extern repv Qiconify_window, Quniconify_window;
+@@ -158,7 +158,7 @@ extern void frames_init (void);
+ extern void frames_kill (void);
+ 
+ /* from functions.c */
+-extern repv Qroot, Qafter_restacking_hook, Qposition, Qspacing;
++extern repv Qafter_restacking_hook, Qposition, Qspacing;
+ extern repv Fdelete_window (repv win);
+ extern repv Fdestroy_window (repv win);
+ extern repv Frestack_windows (repv list);
+diff --git a/src/windows.c b/src/windows.c
+index eef835bd..c1cf652f 100644
+--- src/windows.c
++++ src/windows.c
+@@ -75,7 +75,6 @@ DEFSYM(north_west, "north-west");
+ DEFSYM(north, "north");
+ DEFSYM(north_east, "north-east");
+ DEFSYM(west, "west");
+-DEFSYM(center, "center");
+ DEFSYM(east, "east");
+ DEFSYM(south_west, "south-west");
+ DEFSYM(south, "south");
+@@ -1845,7 +1844,6 @@ windows_init (void)
+     rep_INTERN(north);
+     rep_INTERN(north_east);
+     rep_INTERN(west);
+-    rep_INTERN(center);
+     rep_INTERN(east);
+     rep_INTERN(south_west);
+     rep_INTERN(south);