Remove the error-prone TARGET_CPU_SMP from system/core.

This means that code that uses libcutils no longer has to ensure that
it's set ANDROID_SMP in the calling code's Android.mk for this to
function correctly.

Change-Id: I80c7ff170cd621106f34d6b74689d6b4f03e4eb7
Merge "Remove the error-prone TARGET_CPU_SMP from system/core."