Compiler version comparison logic may not be valid

https://github.com/intel/linux-sgx/blob/4887b30b519d7bfc9f5de6e6330bc0034cce3d75/SampleCode/LocalAttestation/EnclaveInitiator/Makefile#L82

On my machine, shouldn't the result be 0?
```
[root@localhost linux-sgx-sgx_2.15.1]# expr "`cc -dumpversion`" \< "4.9"
1
[root@localhost linux-sgx-sgx_2.15.1]# cc -dumpversion
10.3.1
```

Start at SampleCode/LocalAttestation/EnclaveInitiator/Makefile line 82 and compare the current expr behavior with the reported cc -dumpversion output. Check nearby build logic and existing version checks, then verify the result with the repository's documented build or relevant Makefile target; done means compiler-version handling gives the intended outcome for the reported version.

Written by the indexing model from the issue text.