Add Steven and Philippe to OWNERS and CODEOWNERS

They already have maintain perms on this repo, but we only recently
added the OWNERS files.

Signed-off-by: Nic Cope <nicc@rk0n.org>

Author: negz

CODEOWNERS

@@ -19,4 +19,4 @@
 # See also OWNERS.md for governance details
 
 # Fallback owners
-*			@sergenyalcin @turkenf @negz
+*			@sergenyalcin @turkenf @negz @stevendborrelli @phisco

OWNERS.md

@@ -14,5 +14,7 @@ repository maintainers in their own `OWNERS.md` file.
 * Nic Cope <negz@upbound.com> ([negz](https://github.com/negz))
 * Sergen Yalcin <sergen@upbound.com> ([sergenyalcin](https://github.com/sergenyalcin))
 * Fatih Turken <fatih@upbound.com> ([turkenf](https://github.com/turkenf))
+* Steven Borrelli <steven@upbound.io> ([stevendborrelli](https://github.com/stevendborrelli))
+* Philippe Scorsolini <philippe.scorsolini@upbound.io> ([phisco](https://github.com/phisco))
 
 See [CODEOWNERS](./CODEOWNERS) for automatic PR assignment.