[clang] [OpenCL] Allow undefining cl_khr_integer_dot_product features macros (PR #162055)

[Wenju He via cfe-commits]

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@@ -53,6 +53,13 @@
 #define __opencl_c_kernel_clock_scope_work_group 1
 #define __opencl_c_kernel_clock_scope_sub_group 1
 
+#ifdef __undef___opencl_c_integer_dot_product_input_4x8bit
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wenju-he wrote:

> Perhaps move this down to the section that starts with the comment `// Undefine any feature macros that`...

that section is guarded by OpenCL 3.0: `#if (__OPENCL_CPP_VERSION__ == 202100 || __OPENCL_C_VERSION__ == 300)`
But this section is guarded by OpenCL 2.0 and above.

https://github.com/llvm/llvm-project/pull/162055