[Hexagon] Adding lit exception if Hexagon isn't built.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223335 91177308-0d34-0410-b5e6-96231b3b80d8
Add missing test dependency and use a more canonical target name.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223336 91177308-0d34-0410-b5e6-96231b3b80d8
Revert "Add missing test dependency and use a more canonical target name."

This reverts commit r223336.

NAKAMURA Takumi did the same thing in r223332!

Sorry about the noise.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223337 91177308-0d34-0410-b5e6-96231b3b80d8