cmake: fix JNI configuration problem for Android samples
cmake: fix JNI configuration problem for Android samples

Some CMake 3.x (2.8.12.2 is fine) provides broken build configurations
with following build error message:
    ld: fatal error: -soname: must take a non-empty argument

Linker command line sample contains this:
"-shared -Wl,-soname, -o"

opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv,opencv/opencv