meta-phosphor: move all services to multi-user.target

Instead of obmc-standby.target, use multi-user.target.  This can be
accomplished by changing the definition of SYSTEMD_DEFAULT_TARGET first,
however, the explosive approach by removing that variable and
hard-coding multi-user.target provides a single-step.

Note: This patchset represents effectively the wholesale change of all
services in the meta-phosphor layer as well as the targets.  There are
other parts of OpenBMC that leverage the default variable.

Change-Id: I2b3b2274dd6b32d3832d6e768c26b2607f0ce71c
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/recipes-phosphor/host/phosphor-host-postd_git.bb b/recipes-phosphor/host/phosphor-host-postd_git.bb
index 5692eb9..e1114e8 100644
--- a/recipes-phosphor/host/phosphor-host-postd_git.bb
+++ b/recipes-phosphor/host/phosphor-host-postd_git.bb
@@ -25,10 +25,9 @@
 SERVICE_FILE = "lpcsnoop.service"
 SYSTEMD_PACKAGES = "${PN}"
 SYSTEMD_SERVICE_${PN} += "${SERVICE_FILE}"
-SYSTEMD_DEFAULT_TARGET ?= "obmc-standby.target"
 
 EXTRA_OECONF = " \
   SNOOP_DEVICE="${SNOOP_DEVICE}" \
   POST_CODE_BYTES="${POST_CODE_BYTES}" \
-  SYSTEMD_TARGET="${SYSTEMD_DEFAULT_TARGET}" \
+  SYSTEMD_TARGET="multi-user.target" \
 "