Added parens around cast in Select visitor (OpenCL C compiler issue workaround)
Added parens around cast in Select visitor (OpenCL C compiler issue workaround)


Former-commit-id: 2d754490252e862e2a02b7124270262e62611986
darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide