[PATCH] Un-mathom Perl_save_I16

Change 31016 added a SAVEI16 to toke.c, and change 31023 added a
SAVEI16 to utf8.c.  Therefore, move Perl_save_I16 from from mathom.c
back to scope.c.

• [PATCH] Un-mathom Perl_save_I16 by Jerry D. Hedden
• Re: [PATCH] Un-mathom Perl_save_I16 by Rafael Garcia-Suarez