SPV Version: Emit the requested SPIR-V version, not the header version.

Fixes #1236.
diff --git a/Test/baseResults/hlsl.structbuffer.frag.out b/Test/baseResults/hlsl.structbuffer.frag.out
index 1f4f661..dbc78c7 100644
--- a/Test/baseResults/hlsl.structbuffer.frag.out
+++ b/Test/baseResults/hlsl.structbuffer.frag.out
@@ -187,7 +187,7 @@
 0:?     '@entryPointOutput' (layout( location=0) out 4-component vector of float)
 0:?     'pos' (layout( location=0) flat in uint)
 
-// Module Version 10200
+// Module Version 10000
 // Generated by (magic number): 80003
 // Id's are bound by 96