[parser] remove outdated js_of_ocaml version check from Makefile
[parser] remove outdated js_of_ocaml version check from Makefile

Summary: we only support js_of_ocaml > 3.0

Reviewed By: gabelevi

Differential Revision: D6667097

fbshipit-source-id: 52bafc6db8d923db4c709fbc86d9f5df35ca4ef3

facebook/flow,nmote/flow,facebook/flow,gabelevi/flow,claudiopro/flow,mroch/flow,facebook/flow,jamesgpearce/flow,jamesgpearce/flow,facebook/flow,gabelevi/flow,samwgoldman/flow,popham/flow,claudiopro/flow,mroch/flow,jamesgpearce/flow,claudiopro/flow,jamesgpearce/flow,facebook/flow,popham/flow,samwgoldman/flow,samwgoldman/flow,nmote/flow,JonathanUsername/flow,JonathanUsername/flow,gabelevi/flow,nmote/flow,jamesgpearce/flow,AgentME/flow,samwgoldman/flow,nmote/flow,JonathanUsername/flow,mroch/flow,samwgoldman/flow,facebook/flow,JonathanUsername/flow,nmote/flow,facebook/flow,AgentME/flow,mroch/flow,popham/flow,JonathanUsername/flow,AgentME/flow,mroch/flow,popham/flow,jamesgpearce/flow,JonathanUsername/flow,gabelevi/flow,gabelevi/flow,samwgoldman/flow,popham/flow,nmote/flow,claudiopro/flow,mroch/flow,nmote/flow,AgentME/flow,popham/flow,gabelevi/flow,samwgoldman/flow,JonathanUsername/flow,AgentME/flow,mroch/flow,gabelevi/flow,popham/flow,jamesgpearce/flow,claudiopro/flow