defer/rcuapi: Consistently use dashes for 'RCU-protected' and 'update-side'

Only one sentence is not placing a 'dash' between two words: 'RCU
protected' and 'update side'.  This commit adds dashes for better
consistency.

Signed-off-by: SeongJae Park <sj38.park@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
1 file changed