staging: sm750fb: add required spaces around C operators

Add spaces according to checkpatch.pl messages:
"ERROR: spaces required around that '=' (ctx:VxV)"
"ERROR: need consistent spacing around '-' (ctx:WxV)"
"ERROR: spaces required around that '?' (ctx:VxE)"
"ERROR: need consistent spacing around '&' (ctx:VxW)"

Signed-off-by: Anatoly Stepanov <drivengroove@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>