Fix regression on 'opam upgrade <package>' upgrading unrelated things

Regression introduced in 4db0c13, which is
dedicated to a different case (functionality of this patch is preserved)

Author: AltGr

src/client/opamClient.ml

@@ -113,7 +113,7 @@ let compute_upgrade_t
         | Some nv -> not (OpamPackage.Set.mem nv (Lazy.force t.available_packages)))
       atoms
   in
-  let criteria = if to_install = [] then `Upgrade else `Default in
+  let criteria = if to_install = [] && all then `Upgrade else `Default in
   if all then
     names,
     OpamSolution.resolve t Upgrade

tests/reftests/upgrade.test

@@ -402,16 +402,23 @@ depends: "foo"
 opam-version: "2.0"
 ### opam upgrade baz
 The following actions will be performed:
-=== upgrade 2 packages
+=== upgrade 1 package
   - upgrade baz 1 to 2
-  - upgrade foo 3 to 4 [required by baz]
 
 <><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
 -> removed   baz.1
+-> installed baz.2
+Done.
+### opam upgrade
+The following actions will be performed:
+=== recompile 1 package
+  - recompile baz 2      [uses foo]
+=== upgrade 1 package
+  - upgrade   foo 3 to 4
+
+<><> Processing actions <><><><><><><><><><><><><><><><><><><><><><><><><><><><>
+-> removed   baz.2
 -> removed   foo.3
 -> installed foo.4
 -> installed baz.2
 Done.
-### opam upgrade
-Already up-to-date.
-Nothing to do.