linux_6_12: 6.12.14 -> 6.12.15

pkgs/os-specific/linux/kernel/kernels-org.json

···
         "hash": "sha256:1z2913y38clnlmhvwj49h7p4pic24s4d8np7nmd4lk7m2xz8w532"
     },
     "6.12": {
-        "version": "6.12.14",
-        "hash": "sha256:054gi5fp60d2536z06b1lmys9zlraixh22yb75z42xfqnjzz88wl"
+        "version": "6.12.15",
+        "hash": "sha256:02k3yzlri0h9s4hcx20sif5jvafhjk9vab9h6wsca8hfxa2bvxaz"
     },
     "6.13": {
         "version": "6.13.3",