Add native function to libxmu_1.1.0.bb file because qt3 native depends on its native.
(From OE-Core rev: eeaf7ce29af358ede32ecb64fe15fd9c0e537ad7)
Signed-off-by: Xiaofeng Yan <xiaofeng.yan@windriver.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>