treewide: clean up use of OBMC_MACHINE_FEATURES

Modify the machine meta-layer configs to remove the use of the
OBMC_MACHINE_FEATURES indirection and favor the Yocto MACHINE_FEATURES
variable instead.

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: Ifafb79e4e4c010e9476b9547cd4982f5b645060e
diff --git a/meta-fii/meta-kudo/conf/machine/kudo.conf b/meta-fii/meta-kudo/conf/machine/kudo.conf
index 9f64c47..e065f20 100644
--- a/meta-fii/meta-kudo/conf/machine/kudo.conf
+++ b/meta-fii/meta-kudo/conf/machine/kudo.conf
@@ -22,7 +22,7 @@
 
 SERIAL_CONSOLES = "115200;ttyS0"
 
-OBMC_MACHINE_FEATURES += " \
+MACHINE_FEATURES += " \
     obmc-host-ipmi \
     obmc-phosphor-fan-mgmt \
     obmc-phosphor-flash-mgmt \