witherspoon: enable obmc-ubi-fs feature

Switch Witherspoon to the UBI-based code update mechanism.

Change-Id: Ic89b134654c34f02c3068bb63cf265f79508f1b1
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/meta-witherspoon/conf/machine/witherspoon.conf b/meta-witherspoon/conf/machine/witherspoon.conf
index 078d29c..1d9e6f7 100644
--- a/meta-witherspoon/conf/machine/witherspoon.conf
+++ b/meta-witherspoon/conf/machine/witherspoon.conf
@@ -3,7 +3,7 @@
 
 UBOOT_MACHINE = "ast_g5_ncsi_config"
 
-OBMC_MACHINE_FEATURES += "obmc-mrw openpower-ubi-fs"
+OBMC_MACHINE_FEATURES += "obmc-mrw obmc-ubi-fs openpower-ubi-fs"
 
 PREFERRED_PROVIDER_virtual/p9-vcs-workaround = 'vcs-pre-post'