Remove dead-code infinite loop

Commit d32f5d87 added a 'goto end;' statement
at the end of the code block for the 'end' label.  Fortunately, it was after a
return statement, so no infinite loop occurred, but it is still dead code.

Remove the extra goto statement as cleanup.

Reviewed-by: Matt Caswell <matt@openssl.org>
Reviewed-by: Richard Levitte <levitte@openssl.org>