Add more missing definitions in art::arm::CodeGeneratorARMVIXL.

This fixes build breakages on the read barrier
configuration.  These are just dummy definitions, as ART's
AArch32 VIXL back end is work in progress.

Test: ART_USE_READ_BARRIER=true make
Change-Id: I8a0dd9724e4bf95664330232db40fd58bb8d234e
1 file changed