build: mozilla: don't explicitly set the compiler target
* as newer mozilla builds will fail with this set (nspr build problem)

(integrated from komodo (trunk) change 85084 by toddw)

git-svn-id: http://svn.openkomodo.com/repos/openkomodo/trunk@14353 b87d16e7-d29f-4ee1-b5ec-817d645d335f