set a prebuilt directory name for the 2nd arch
set a prebuilt directory name for the 2nd arch

In order to install 32-bit gdbserver on a 64-bit build,
prebuilts/misc/Android.mk needs to know the prebuilt directory name
for the 2nd arch.

Change-Id: Ibc943b758eb9404f7f5f9fbbd8720cc67f6a6f01

xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build,xorware/android_build