Corrections to processing abioverride flag

Bug: 28043974

One of the parameters to Settings class wrongly passes the secondaryCpuAbi
as CpuAbiOverrideString causing mayhem for multiarch libraries. Use the
correct param.

Further, for multiarch, the cpuabioverride flag is ignored. Remove the
check for cpuabioverride when checking for use32bitabi flag.

Change-Id: I7eff057031e3ddb18fcce6f380658a522af8b64d