[views/forms] Fix EntityFieldsForm.link_to when parent entity is being created
When the parent entity is being created and the inlined form is displayed, the
parent entity has no eid yet and `peid` is usually 'A'. So int() raises a
ValueError.
Closes #4627739.
\.svn
^build$
^dist$
\.pyc$
\.pyo$
\.bak$
\.old$
\~$
\#.*?\#$
\.swp$
^doc/book/en/apidoc$
\.old$
syntax: regexp
.*/data/database/.*\.sqlite
.*/data/database/.*\.config
.*/data/database/tmpdb.*
.*/data/ldapdb/.*
^doc/html/
^doc/doctrees/
^doc/book/en/devweb/js_api/
data/pgdb/