This effects the reported scale of the raw values, and thus userspace
applications that use this value.

One micro tesla equal 0.01 gauss. So I have fixed calculation formula And add RAW_TO_GAUSS macro.
ASA is in the range of 0 to 255. If multiply 0.003, calculation result(in_magn_[*]_scale) is
always 0. So multiply 3000 and return and IIO_VAL_INT_PLUS_MICRO.
As a result, read_raw call back function return accurate scale value.
Signed-off-by: Beomho Seo <beomho.seo@samsung.com>
Cc: stable@vger.kernel.org
Signed-off-by: Jonathan Cameron <jic23@kernel.org>