Add missing WGSL intrinsics to test

Closes shader-slang#5263

tests/autodiff/custom-intrinsic-1.slang

@@ -1,7 +1,6 @@
 //TEST(compute, vulkan):COMPARE_COMPUTE_EX:-vk -compute -shaderobj -output-using-type
 //TEST(compute):COMPARE_COMPUTE_EX:-slang -compute -shaderobj -output-using-type
-// slang-test/WGPU: IR opcode during code emit #5263
-//DISABLE_TEST(compute):COMPARE_COMPUTE_EX:-wgpu
+//TEST(compute):COMPARE_COMPUTE_EX:-wgpu
 
 //TEST_INPUT:ubuffer(data=[0 0 0 0 0], stride=4):out,name=outputBuffer
 RWStructuredBuffer<float> outputBuffer;
@@ -19,6 +18,7 @@ namespace myintrinsiclib
     __target_intrinsic(cpp, "$P_exp($0)")
     __target_intrinsic(spirv, "12 resultType resultId glsl450 27 _0")
     __target_intrinsic(metal, "exp($0)")
+    __target_intrinsic(wgsl, "exp($0)")
     [ForwardDerivative(d_myexp<T>)]
     T myexp(T x);
 
@@ -39,6 +39,7 @@ namespace myintrinsiclib
     __target_intrinsic(cuda, "$P_sin($0)")
     __target_intrinsic(cpp, "$P_sin($0)")
     __target_intrinsic(spirv, "12 resultType resultId glsl450 13 _0")
+    __target_intrinsic(wgsl, "sin($0)")
     [ForwardDerivative(d_mysin<T>)]
     T mysin(T x);
 
@@ -58,6 +59,7 @@ namespace myintrinsiclib
     __target_intrinsic(cuda, "$P_cos($0)")
     __target_intrinsic(cpp, "$P_cos($0)")
     __target_intrinsic(spirv, "12 resultType resultId glsl450 14 _0")
+    __target_intrinsic(wgsl, "cos($0)")
     [ForwardDerivative(d_mycos<T>)]
     T mycos(T x);