simple add with swizzle and mul with swizzle tests

progs/fp/add-swz.txt

@@ -0,0 +1,5 @@
+!!ARBfp1.0
+TEMP R0;
+ADD R0, fragment.color, fragment.color;
+ADD result.color, R0.xxxx, R0;
+END

progs/fp/mul-swz.txt

@@ -0,0 +1,3 @@
+!!ARBfp1.0
+MUL result.color, fragment.color.zyxw, fragment.color;
+END