openpower: machine-xml: Remove blank help section

op-build/openpower/package/machine-xml/Config.in:7: warning:
'BR2_PACKAGE_MACHINE_XML' defined with blank help text

Signed-off-by: Joel Stanley <joel@jms.id.au>
diff --git a/openpower/package/machine-xml/Config.in b/openpower/package/machine-xml/Config.in
index 3dedcfd..c1064d7 100755
--- a/openpower/package/machine-xml/Config.in
+++ b/openpower/package/machine-xml/Config.in
@@ -4,7 +4,6 @@
         bool "machine_xml"
         default y if (BR2_OPENPOWER_PLATFORM)
         select BR2_PACKAGE_COMMON_P8_XML if (BR2_OPENPOWER_POWER8)
-        help
 
 choice
 	prompt "Machine XML location"