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

See <deb3c72#commitcomment-29668834>

Author: fluca1978

doc/Language/functions.pod6

@@ -1170,7 +1170,7 @@ Verbosity on
 
 It's possible to alter how arguments are processed before they're passed
 to C<sub MAIN {}> by setting options in C<%*SUB-MAIN-OPTS> hash.  Due to the
-nature of dynamic variables, one needs to set up his or her own C<%*SUB-MAIN-OPTS>
+nature of dynamic variables, it is required to set up C<%*SUB-MAIN-OPTS>
 hash and fill it with the appropriate settings.  For instance:
 
     my %*SUB-MAIN-OPTS =