A suicide attack is an attack in which the attacker or attackers intend to kill others and intend to die in the process (see suicide). In a suicide attack in the strict sense the attacker dies by the attack itself, for example in an explosion or crash caused by the attacker.
The attacker in a suicide attack wants to kill as many people as possible. 
The passage didn't talk about them wanting to kill a lot of people... they may want to kill lots or some may just have a few people they want to kill. There is no way to know. 
( z0 want :ARG0 ( z1 person :ARG0-of ( z2 attack ) ) :ARG1 ( z3 kill :ARG0 z1 :ARG1 ( z4 person :quant ( z5 as-many-as :op ( z6 possible ) ) ) ) :time ( z7 attack :ARG0 z1 :manner ( z8 suicide ) ) )
(z0 / want-01
    :ARG0 (z1 / person
              :ARG0-of (z2 / attack-01))
    :ARG1 (z3 / kill-01
              :ARG0 z1
              :ARG1 (z4 / person
                        :quant (z5 / as-many-as
                                   :op1 (z6 / possible-01))))
    :time (z7 / attack-01
              :ARG0 z1
              :manner (z8 / suicide)))
The attacker in a suicide attack wants to kill as many people as possible .
z1 :ARG0-of z2
z7 :manner z8
z7 :ARG0 z1
z0 :time z7
z0 :ARG0 z1
z0 :ARG1 z3
z3 :ARG0 z1
z4 :quant z5
z3 :ARG1 z4
z5 :op1 z6