Revert "Temporarily disable building the armv7 variants of profile_ios on"

This reverts commit r184816.  With Chandler's change in r184929, this should
no longer be necessary.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@184961 91177308-0d34-0410-b5e6-96231b3b80d8