[clang] [CIR] Change vectorize_enable loop hint to a bool. (PR #235148)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -24,8 +24,8 @@ cir.func @loops(%c: !cir.bool) {
     cir.yield
   } step {
     cir.yield
-  // CHECK: } loop_id distinct{{\[[0-9]+\]}}<> loop_hints < must_progress vectorize_enable vectorize_width = 4 vectorize_scalable = true vectorize_predicate = false interleave_count = 2 unroll = enable unroll_count = 8 distribute = true>
-  } loop_id distinct[4]<> loop_hints < must_progress vectorize_enable vectorize_width = 4 vectorize_scalable = true vectorize_predicate = false interleave_count = 2 unroll = enable unroll_count = 8 distribute = true>
+  // CHECK: } loop_id distinct{{\[[0-9]+\]}}<> loop_hints < must_progress vectorize_enable = true vectorize_width = 4 vectorize_scalable = true vectorize_predicate = false interleave_count = 2 unroll = enable unroll_count = 8 distribute = true>
+  } loop_id distinct[4]<> loop_hints < must_progress vectorize_enable = true vectorize_width = 4 vectorize_scalable = true vectorize_predicate = false interleave_count = 2 unroll = enable unroll_count = 8 distribute = true>
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bcardosolopes wrote:

nit: add a `vectorize_enable = false` round-trip too, since that state is the reason for the change.

https://github.com/llvm/llvm-project/pull/235148