Build both 32bit and 64bit binaries for resolv tests

This is a workaround for MTS coverage which can only be ran in
cf_x86_phone (32-bit).
Because the test_suite target is 64 bit and the test infra is running
the 64 bit test suite on cf_x86_phone (32-bit) for coverage.

Bug: 152303924
Test: m mts && mts-tradefed run mts-dnsresolver
Test: mts-tradefed run mts-dnsresolve against cf_x86_phone
Change-Id: Ieddc420db764d52698422a9e8c8f95842f88838d