HLSL: fix type on clip/cull index result

While adding geometry stage support for clip/cull, it transpired that the
existing clip/cull support was not setting the type of the result of indexing
into the clup/cull variable.  That's a defect independent of the geometry
support, so to simplify the geometry PR, this is addressed separately.

It doesn't appear to change the generated SPIR-V, but that's probably down to
something else tolerating a bad input.
diff --git a/Test/baseResults/hlsl.clipdistance-8.frag.out b/Test/baseResults/hlsl.clipdistance-8.frag.out
index a1f6648..6777efa 100644
--- a/Test/baseResults/hlsl.clipdistance-8.frag.out
+++ b/Test/baseResults/hlsl.clipdistance-8.frag.out
@@ -43,7 +43,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                0 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                0 (const int)
@@ -55,7 +55,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                1 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                1 (const int)
@@ -67,7 +67,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                2 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                2 (const int)
@@ -77,7 +77,7 @@
 0:?               'v' ( temp structure{ temp 4-component vector of float Position,  temp 3-component vector of float clip0,  temp float clip1})
 0:8              Constant:
 0:8                2 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                3 (const int)
@@ -138,7 +138,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                0 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                0 (const int)
@@ -150,7 +150,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                1 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                1 (const int)
@@ -162,7 +162,7 @@
 0:8                  1 (const int)
 0:8              Constant:
 0:8                2 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                2 (const int)
@@ -172,7 +172,7 @@
 0:?               'v' ( temp structure{ temp 4-component vector of float Position,  temp 3-component vector of float clip0,  temp float clip1})
 0:8              Constant:
 0:8                2 (const int)
-0:8            direct index ( temp float)
+0:8            direct index ( in float ClipDistance)
 0:?               'v.clip1' ( in 4-element array of float ClipDistance)
 0:8              Constant:
 0:8                3 (const int)