Add __popcountsi2 to the function compat list.

This is needed if we use Clang to compile Bionic, which won't include
__popcountsi2 anymore as Clang generates inline instructions. However
prebuilt binary blobs still depend on libc.so to resolve __popcountsi2.

Change-Id: I9001a3884c4be250c0ceebcd79922783fae1a0b7
Re-export libgcc's __aeabi_uidivmod and __popcount_tab

This is required to make the Nexus 10 graphics driver work on a system
compiled with gcc 4.9.

Change-Id: If3f3d488652a736d9ea3e583548d74fae3ffa902
Signed-off-by: Bernhard Rosenkränzer <Bernhard.Rosenkranzer@linaro.org>