weston-init: Fix weston-keyboard path in weston.ini

The weston-keyboard executable is installed into /usr/libexec
instead of /usr/lib/weston , correct the path in weston.ini .

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Khem Raj <raj.khem@gmail.com>
Cc: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>