doc: update list of aliases for the env command

* add link to askenv man-page
* add printenv

Signed-off-by: Heinrich Schuchardt <heinrich.schuchardt@canonical.com>

doc/usage/cmd/env.rst

@@ -40,9 +40,10 @@ the UEFI variables.
 
 The next commands are kept as alias and for compatibility:
 
-+ *askenv* = *env ask*
++ :doc:`askenv <askenv>` = *env ask*
 + *editenv* = *env edit*
 + *grepenv* = *env grep*
++ :doc:`printenv <printenv>` = *env print*
 + *run* = *env run*
 + *setenv* = *env set*