Some miscellaneous fixes

-ndless_resources should work if syscall-addrs.h weren't broken.
-Move MakeSyscalls to ndless-sdk/tools
-Add seperation for OS versions in syscall-addrs.h
-Fix Zehn offset in resources-loader
-Add "-fPIE" in build_toolchain.sh
-Remove manual relocations in ndless_resources
-Set ndless_resources' entry to main