ARM: Remove VIXL dependency from ArmManagedRegister.

Also remove unnecesary DWARF includes.

Motivation: Preparing to move JNI calling conventions
to runtime/ to unify the GenericJNI frame creation with
the JNI compiler.

Test: Rely on TreeHugger.
Change-Id: If8afc4a4fa41e41f0242962bb225b36633c1c153
7 files changed