staging: sm750fb: add spaces around operators

Add spaces around operators -, *, ?:, >>, << to conform to kernel style.
These instances were found with checkpatch.pl

Signed-off-by: Katie Dunne <kdunne@mail.ccsf.edu>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>