meson: look for linux/input-event-codes.h with libwayland flags

On DragonFly and FreeBSD native evdev headers are not not be used
outside of base system. Linux-compatible headers are provided by
evdev-proto package but require extra flags. As evdev-proto lacks
pkg-config support use libwayland prefix as approximation.

meson.build:974:0: ERROR: C header 'linux/input-event-codes.h' not usable

meson.build

@@ -988,7 +988,9 @@ wayland = {
              dependency('wayland-cursor', version: '>= 1.20.0', required: get_option('wayland')),
              dependency('wayland-protocols', version: '>= 1.25', required: get_option('wayland')),
              dependency('xkbcommon', version: '>= 0.3.0', required: get_option('wayland'))],
-    'header': cc.has_header('linux/input-event-codes.h', required: get_option('wayland')),
+    'header': cc.has_header('linux/input-event-codes.h', required: get_option('wayland'),
+                            # Pass CFLAGS from a related package as a hint for non-Linux
+                            dependencies: dependency('wayland-client', required: get_option('wayland'))),
     'scanner': find_program('wayland-scanner', required: get_option('wayland')),
 }
 wayland_deps = true