Makefile: strip debugging informations only

--strip-unneeded causes SIGSEGV when accessing g_executable_path. So
test_libvpx crashes due to SIGSEGV in ::testing::InitGoogleTest().

OS/2, aout, strip v2.23.2

Change-Id: I2718d082447ee0d9ad0c021b9156c50e1ac085a6
1 file changed