Add Android.mk

1.add the Android.mk to support android system build;
2.add config options CFG_TEE_CLIENT_LOG_FILE/CFG_TEE_SUPP_LOG_FILE/
  CFG_TEE_CLIENT_LOAD_PATH to common config.mk.

Signed-off-by: sunny <sunny@allwinnertech.com>
Reviewed-by: Pascal Brand <pascal.brand@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>
Reviewed-by: Joakim Bech <joakim.bech@linaro.org>
Tested-by: sunny <sunny@allwinnertech.com> (Allwinner A80 platform)