krb5: fix path to recipe and upgrade to 1.11

* drop PR
* fix FILES_${PN}-doc
* fix QA warnings:
  WARNING: QA Issue: krb5: Files/directories were installed but not
  shipped
    /usr/share/gnats
    /usr/share/gnats/mit
  and RPATH entries

Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>