Fix configuration for ANDROID_VERSION to have a value in all cases

When configured without setting a linker version explicitly through --enable-alinker a
specific android version is never set but the gingerbread linker. The version should be
set to a default value as well.

Signed-off-by: Simon Busch <morphis@gravedo.de>
Use a specific version configuration file instead of build time config.h

Signed-off-by: Simon Busch <morphis@gravedo.de>