meson: install native file in sdk

Without a native environment file, find_program() can't
locate the native program inside SDK.

That stops wayland compositor using wayland scanner.

Signed-off-by: Hsia-Jun(Randy) Li <randy.li@synaptics.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>