lib/systems: fix scaleway-c1 platform

This regressed in 9c213398b312e0f0bb9cdf05090fd20223a82ad0

The recursiveUpdate gave the platform both gcc.cpu and gcc.arch attrs
instead of only gcc.cpu. This is invalid; gcc configuration fails with:

```
Switch "--with-arch" may not be used with switch "--with-cpu"
```

So we revert to using `//` to retain only gcc.cpu
(which is more specific than the processor arch).

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/systems/platforms.nix b/lib/systems/platforms.nix
index d7efe84e2b85..2a5f630c3de9 100644
--- a/lib/systems/platforms.nix
+++ b/lib/systems/platforms.nix
@@ -233,7 +233,7 @@ rec {
     };
   };
 
-  scaleway-c1 = lib.recursiveUpdate armv7l-hf-multiplatform {
+  scaleway-c1 = armv7l-hf-multiplatform // {
     gcc = {
       cpu = "cortex-a9";
       fpu = "vfpv3";