chassis: Rename FMT variable in control power

In order to disambiguate from other uses of the FMT variable name,
rename to OBMC_CONTROL_POWER_FMT in obmc-op-control-power bit bake
files. Change was suggested in the following review:
https://gerrit.openbmc-project.xyz/c/openbmc/openbmc/+/50765

Signed-off-by: Jim Wright <jlwright@us.ibm.com>
Change-Id: If74dc281b8dfa9c06b86012f010d5b5a40d1a0f6
diff --git a/meta-ibm/recipes-phosphor/chassis/obmc-op-control-power_%.bbappend b/meta-ibm/recipes-phosphor/chassis/obmc-op-control-power_%.bbappend
index 8bfef20..5c309e2 100644
--- a/meta-ibm/recipes-phosphor/chassis/obmc-op-control-power_%.bbappend
+++ b/meta-ibm/recipes-phosphor/chassis/obmc-op-control-power_%.bbappend
@@ -3,4 +3,4 @@
 # Remove, from the p10bmc image, the service file that starts the skeleton power
 # control application. That image will use the power control application
 # included in the phosphor-power repository.
-DBUS_SERVICE:${PN}:remove:p10bmc = "${@compose_list(d, 'FMT', 'OBMC_POWER_INSTANCES')}"
+OBMC_CONTROL_POWER_FMT:p10bmc = ""