rhel9: add dropin to disable grub timer

This will disable the grub-boot-success timer if greenboot exists to
ensure greenboot functions correctly and the timer does not modify the
boot_success flag when a ssh session persists for more than 2 min. This
customization is added to containerImage and edgeCommitImage.

Signed-off-by: Sayan Paul <paul.sayan@gmail.com>

pkg/distro/rhel9/images.go

@@ -299,6 +299,18 @@ func edgeCommitImage(workload workload.Workload,
 	if !common.VersionLessThan(t.arch.distro.osVersion, "9.2") || t.arch.distro.osVersion == "9-stream" {
 		img.OSCustomizations.EnabledServices = append(img.OSCustomizations.EnabledServices, "ignition-firstboot-complete.service", "coreos-ignition-write-issues.service")
 	}
+	img.OSCustomizations.SystemdUnit = []*osbuild.SystemdUnitStageOptions{
+		{
+			Unit:     "grub-boot-success.timer",
+			Dropin:   "10-disable-if-greenboot.conf",
+			UnitType: osbuild.Global,
+			Config: osbuild.SystemdServiceUnitDropin{
+				Unit: &osbuild.SystemdUnitSection{
+					FileExists: "!/usr/libexec/greenboot/greenboot",
+				},
+			},
+		},
+	}
 	img.Environment = t.environment
 	img.Workload = workload
 
@@ -334,6 +346,19 @@ func edgeContainerImage(workload workload.Workload,
 		img.OSCustomizations.EnabledServices = append(img.OSCustomizations.EnabledServices, "ignition-firstboot-complete.service", "coreos-ignition-write-issues.service")
 	}
 
+	img.OSCustomizations.SystemdUnit = []*osbuild.SystemdUnitStageOptions{
+		{
+			Unit:     "grub-boot-success.timer",
+			Dropin:   "10-disable-if-greenboot.conf",
+			UnitType: osbuild.Global,
+			Config: osbuild.SystemdServiceUnitDropin{
+				Unit: &osbuild.SystemdUnitSection{
+					FileExists: "!/usr/libexec/greenboot/greenboot",
+				},
+			},
+		},
+	}
+
 	return img, nil
 }