added constant propagation for sqrt_f32 and tests.
added constant propagation for sqrt_f32 and tests.


Former-commit-id: b4649510603c5b761747dd99248823f1d9368ae6
Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide,Trass3r/Halide,darkbuck/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,Trass3r/Halide,darkbuck/Halide,darkbuck/Halide,darkbuck/Halide