genxml: Add XML version tags

There's not much point to having them or not having them but this
reduces some pointless diff from the version we can auto-generate

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>

src/intel/genxml/gen4.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="BRW" gen="4">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>

src/intel/genxml/gen45.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="CTG" gen="4.5">
   <enum name="3D_Vertex_Component_Control" prefix="VFCOMP">
     <value name="NOSTORE" value="0"/>

src/intel/genxml/gen5.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="ILK" gen="5">
   <struct name="RENDER_SURFACE_STATE" length="6">
     <field name="Surface Type" start="29" end="31" type="uint">

src/intel/genxml/gen6.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="SNB" gen="6">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>

src/intel/genxml/gen7.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="IVB" gen="7">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>

src/intel/genxml/gen75.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="HSW" gen="7.5">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>

src/intel/genxml/gen8.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="BDW" gen="8">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>

src/intel/genxml/gen9.xml

@@ -1,3 +1,4 @@
+<?xml version="1.0" ?>
 <genxml name="SKL" gen="9">
   <enum name="3D_Prim_Topo_Type" prefix="3DPRIM">
     <value name="POINTLIST" value="1"/>