Stop setting OTHER_OPTIONS in JavaScriptCore's Makefile.

It's not necessary to pass "-target All" as xcodebuild always builds the
first target in the project unless otherwise specified. The presence of
that option also breaks "make clean" since that results in both the
-target and -alltargets options being passed to xcodebuild.

* Makefile:

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@81805 268f45cc-cd09-0410-ab3c-d52691b4dbfc