Compile libbtcore and libosi for host

The static libraries now also compile for a Linux host as libbtcore-host and
libosi-host. The unittests are compiled for the target against Bionic libc and
for the host against glibc.

Bug: 22884515
Change-Id: Iac1310a48cfd2ff43c356cb31165fd176d0e1d39
2 files changed