Fix ambigous statement about %*SUB-MAIN-OPTS.
Fix ambigous statement about %*SUB-MAIN-OPTS.

See <https://github.com/perl6/doc/commit/deb3c72da775510bc6fd356f5f6b712bb8bc08d8#commitcomment-29668834>

dmaestro/doc,MasterDuke17/doc,MasterDuke17/doc,stmuk/doc,dmaestro/doc,perl6/doc,perl6/doc,jonathanstowe/doc,MasterDuke17/doc,stmuk/doc,perl6/doc,perl6/doc,tbrowder/doc,dmaestro/doc,jonathanstowe/doc,jonathanstowe/doc,jonathanstowe/doc,tbrowder/doc,MasterDuke17/doc,stmuk/doc,tbrowder/doc,dmaestro/doc,stmuk/doc,jonathanstowe/doc,tbrowder/doc,perl6/doc,dmaestro/doc,stmuk/doc