LDFLAGS are reserved for external interaction via make variable, the
following should work:

$ make LDFLAGS="-L/xxx"
$ LDFLAGS="-L/xxx" make

1. Move internal flags to LOCAL_LDFLAGS
2. Respect external LDFLAGS
3. LDFLAGS should be last linkage flags.

Signed-off-by: Alon Bar-Lev <alon.barlev@gmail.com>