Fix references to sprintf routine

Author: stoned

doc/Language/5to6-perlfunc.pod6

@@ -1391,7 +1391,7 @@ X<| printf - perlfunc>
 =item printf
 
 Raku version is similar; see
-L<sprintf|/type/Str#sub_sprintf> for details
+L<sprintf|/routine/sprintf> for details
 on acceptable format directives. To print to a filehandle other than
 STDOUT, use the L«C<.printf>|/routine/printf» method on that filehandle.
 

doc/Type/IO/Handle.pod6

@@ -573,7 +573,7 @@ Defined as:
 
 Formats a string based on the given format and arguments and C<.print>s the
 result into the filehandle. See
-L<sub sprintf|/type/Str#sub_sprintf> for details on
+L<sprintf|/routine/sprintf> for details on
 acceptable format directives.
 
 Attempting to call this method when the handle is