HLSL: allow uint literals, and add test for numeric suffixes

Test/hlsl.numericsuffixes.frag

@@ -0,0 +1,20 @@
+
+struct PS_OUTPUT { float4 color : SV_Target0; };
+
+PS_OUTPUT main()
+{
+    // Test numeric suffixes
+    float r00 = 1.0f;    // float
+    uint  r01 = 1u;      // lower uint
+    uint  r02 = 2U;      // upper uint
+    uint  r03 = 0xabcu;  // lower hex uint
+    uint  r04 = 0xABCU;  // upper hex uint (upper 0X is not accepted)
+    int   r05 = 5l;      // lower long int
+    int   r06 = 6L;      // upper long int
+    int   r07 = 071;     // octal
+    uint  r08 = 072u;    // unsigned octal
+
+    PS_OUTPUT ps_output;
+    ps_output.color = r07; // gets 71 octal = 57 decimal
+    return ps_output;
+}