bionic libc tests: clean up setting for hello_world.cpp

clean up the remaining settings for hello_world.cpp
in file tests/bionic/libc/Android.mk

Change-Id: I6108a0d7e33c677dd2dba6dde3155f088d3fe14e
Signed-off-by: Yongqin Liu <yongqin.liu@linaro.org>
1 file changed