staging: goldfish: (coding style) Add spaces around the "+" to conform to checkpatch

Added a space around the "+" at: "reg_base+addr2" to clear up a checkpatch check.

Signed-off-by: Christian Colic <colic.christian@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>