Run fbkpatch instead of kpatch

Summary: Subj.

Differential Revision: D64405306

fbshipit-source-id: c4efaab9aa59e89e700383246a53730234a1c9f4

cookbooks/fb_kpatch/recipes/default.rb

@@ -47,3 +47,13 @@
             },
           })
 end
+fb_systemd_override 'fbkpatch' do
+  unit_name 'kpatch.service'
+  content({
+            'Service' => {
+              # Empty record is required! It tells systemd to clean existing
+              # values, as it appends values from drop ins.
+              'ExecStart' => ['', '/usr/local/bin/fbkpatch load --all'],
+            },
+          })
+end