meta-ampere: fix postinstall scriptlets error

Fix compilation error after subtree update:
   ERROR: obmc-phosphor-image-1.0-r0 do_rootfs: Postinstall scriptlets of
      ['ampere-sysfw-hang-handler'] have failed. If the intention is to
      defer them to first boot, then please place them into
      pkg_postinst_ontarget:${PN} ().
   Deferring to first boot via 'exit 1' is no longer supported.

Tested:
1. Compile Mt.Jade and Mt.Mitchell without error
2. Check ampere-boot-progress and ampere-sysfw-hang-handler work.

Signed-off-by: Thang Q. Nguyen <thang@os.amperecomputing.com>
Change-Id: I5d692cb4078df05ac20ace34429463ea4e9c18ca
diff --git a/meta-ampere/meta-common/recipes-ampere/host/ac01-boot-progress/ampere-boot-progress.service b/meta-ampere/meta-common/recipes-ampere/host/ac01-boot-progress/ampere-boot-progress.service
index 06af72a..c74d890 100644
--- a/meta-ampere/meta-common/recipes-ampere/host/ac01-boot-progress/ampere-boot-progress.service
+++ b/meta-ampere/meta-common/recipes-ampere/host/ac01-boot-progress/ampere-boot-progress.service
@@ -6,6 +6,3 @@
 [Service]
 ExecStart=/usr/sbin/ampere_boot_progress.sh
 SyslogIdentifier=ampere-boot-progress
-
-[Install]
-WantedBy=obmc-host-already-on@0.target
diff --git a/meta-ampere/meta-mitchell/recipes-ampere/host/ampere-sysfw-hang-handler/ampere-sysfw-hang-handler.service b/meta-ampere/meta-mitchell/recipes-ampere/host/ampere-sysfw-hang-handler/ampere-sysfw-hang-handler.service
index 7040b3e..84a0e32 100644
--- a/meta-ampere/meta-mitchell/recipes-ampere/host/ampere-sysfw-hang-handler/ampere-sysfw-hang-handler.service
+++ b/meta-ampere/meta-mitchell/recipes-ampere/host/ampere-sysfw-hang-handler/ampere-sysfw-hang-handler.service
@@ -8,6 +8,3 @@
 Type=simple
 ExecStart=/usr/sbin/ampere_sysfw_hang_handler.sh
 SyslogIdentifier=ampere_sysfw_hang
-
-[Install]
-WantedBy=obmc-host-already-on@0.target