aco: assume new generations are unsupported by clrx

clrx hasn't seen any changes since 2021. I guess the only reson to keep it is
GFX6 support.

Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Reviewed-by: Timur Kristóf <timur.kristof@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25522>

src/amd/compiler/aco_print_asm.cpp

@@ -148,9 +148,7 @@ to_clrx_device_name(amd_gfx_level gfx_level, radeon_family family)
       case CHIP_NAVI12: return "gfx1011";
       default: return nullptr;
       }
-   case GFX10_3:
-   case GFX11: return nullptr;
-   default: unreachable("Invalid chip class!"); return nullptr;
+   default: return nullptr;
    }
 }