[JIT/Memory] Fix up semantic of setExecutable().

setExecutable() should do everything that's needed to make the memory
executable on host, i.e. unconditionally set permissions + invalidate
instruction cache. llvm-rtdyld will be updated in my next commit.

Discusseed with: Lang Hames (as part of D13631).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@253341 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed