Fix spelling in perlguts

Author: pjcj

pod/perlguts.pod

@@ -3760,7 +3760,7 @@ in a single byte.
 
 =head2 How do I compare strings?
 
-L<perlapi/sv_cmp> and L<perlapi/sv_cmp_flags> do a lexigraphic
+L<perlapi/sv_cmp> and L<perlapi/sv_cmp_flags> do a lexicographic
 comparison of two SVs, and handle UTF-8ness properly.  Note, however,
 that Unicode specifies a much fancier mechanism for collation, available
 via the L<Unicode::Collate> module.