Disable PRODUCT_ART_USE_READ_BARRIER for MIPS devices

MIPS doesn't yet have support for ART read barriers.

This fixes ART test failures for MIPS.

Test: mma test-art-target on CI20

Change-Id: I258831cf7b3f4a4066ed3f7b0ec2dc3e3f45e234
3 files changed
tree: a679ab5d638999776e495da4e0ab21e5833973d6
  1. arm_krait/
  2. armv8/
  3. mips32r2_fp/
  4. mips32r2_fp_xburst/
  5. mips64r6/
  6. silvermont/