CI: kernel: Trigger workflow for more directories

Trigger the kernel build workflow also for more directories.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
(cherry picked from commit 546822775cd988360964687c0cb430d67bd5c617)

.github/workflows/kernel.yml

@@ -3,8 +3,10 @@ name: Build Kernel
 on:
   pull_request:
     paths:
+      - '.github/workflows/kernel.yml'
       - 'include/kernel-*'
       - 'package/kernel/**'
+      - 'target/linux/generic/**'
 jobs:
   determine_targets:
     name: Set targets