Witherspoon MRW XML revision bump

Fixes the IDs for the Power Limit and PS Derating Factor sensors.

Change-Id: I439a1586edb983c2628db233f24b5d77a7381297
Signed-off-by: Matt Spinler <spinler@us.ibm.com>
diff --git a/meta-openbmc-machines/meta-openpower/meta-ibm/meta-witherspoon/conf/machine/witherspoon.conf b/meta-openbmc-machines/meta-openpower/meta-ibm/meta-witherspoon/conf/machine/witherspoon.conf
index 74cc40d..078d29c 100644
--- a/meta-openbmc-machines/meta-openpower/meta-ibm/meta-witherspoon/conf/machine/witherspoon.conf
+++ b/meta-openbmc-machines/meta-openpower/meta-ibm/meta-witherspoon/conf/machine/witherspoon.conf
@@ -13,7 +13,7 @@
 require conf/machine/include/p9.inc
 
 PHOSPHOR_MRW_URI = "git://github.com/open-power/witherspoon-xml"
-PHOSPHOR_MRW_REV = "317720f56e49c7fb5b4a66bd36082f505ed81317"
+PHOSPHOR_MRW_REV = "f8aaa73b75564d6b845147afd3b2ab7c433838bc"
 
 # Inhibit phosphor-hwmon-config-mrw
 VIRTUAL-RUNTIME_phosphor-hwmon-config = ""