src: throw when -c and -e are used simultaneously

The -c flag ("check script syntax") and -e flag ("evaluate given code")
have contradictory meanings. Make them mutually exclusive by throwing
when both of them are provided.

Fixes: https://github.com/nodejs/node/issues/11680
PR-URL: https://github.com/nodejs/node/pull/11689


Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Richard Lau <riclau@uk.ibm.com>