staging: most: dim2: Replace function dim_norm_ctrl_async_buffer_size()

staging: most: dim2: Replace function dim_norm_ctrl_async_buffer_size()

Remove function dim_norm_ctrl_async_buffer_size as it does nothing
except call norm_ctrl_async_buffer_size.
Rename norm_ctrl_async_buffer_size to dim_norm_ctrl_async_buffer_size to
maintain compatibility with call sites of the latter.
Change type of new dim_norm_ctrl_async_buffer_size from static inline to
non-static to match the old version.
Modify only remaining call site of norm_ctrl_async_buffer_size to call
dim_norm_ctrl_async_buffer_size instead.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Link: https://lore.kernel.org/r/20190708064145.3250-1-nishkadg.linux@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>