arago-source-ipk.conf: Remove linux-stable and use linux
arago-source-ipk.conf: Remove linux-stable and use linux

* The linux stable recipe from oe-classic is now simply linux.
* Tweak arago-source-ipk.conf to reflect that change.

Signed-off-by: Denys Dmytriyenko <d29de71aea38aad3a87d486929cb0aad173ae612@ti.com>

rcn-ee/meta-arago,rcn-ee/meta-arago,MentorEmbedded/meta-arago,rcn-ee/meta-arago,MentorEmbedded/meta-arago,MentorEmbedded/meta-arago,rcn-ee/meta-arago,rcn-ee/meta-arago,MentorEmbedded/meta-arago