Move xkbcommon dynamic loading code into generic linuxbsd folder

Since Wayland uses it too, it only makes sense to have it in the parent
directory of both.

platform/linuxbsd/SCsub

@@ -11,6 +11,7 @@ common_linuxbsd = [
     "joypad_linux.cpp",
     "freedesktop_portal_desktop.cpp",
     "freedesktop_screensaver.cpp",
+    "xkbcommon-so_wrap.c",
 ]
 
 if env["x11"]:

platform/linuxbsd/x11/SCsub

@@ -9,7 +9,6 @@ source_files = [
     "dynwrappers/xcursor-so_wrap.c",
     "dynwrappers/xinerama-so_wrap.c",
     "dynwrappers/xinput2-so_wrap.c",
-    "dynwrappers/xkbcommon-so_wrap.c",
     "dynwrappers/xrandr-so_wrap.c",
     "dynwrappers/xrender-so_wrap.c",
     "dynwrappers/xext-so_wrap.c",

platform/linuxbsd/x11/display_server_x11.h

@@ -75,10 +75,11 @@
 #include "dynwrappers/xext-so_wrap.h"
 #include "dynwrappers/xinerama-so_wrap.h"
 #include "dynwrappers/xinput2-so_wrap.h"
-#include "dynwrappers/xkbcommon-so_wrap.h"
 #include "dynwrappers/xrandr-so_wrap.h"
 #include "dynwrappers/xrender-so_wrap.h"
 
+#include "../xkbcommon-so_wrap.h"
+
 typedef struct _xrr_monitor_info {
 	Atom name;
 	Bool primary = false;