X86Vector: relax checks in rsqrt's integration test

[cota]

Summary

Instead of hard-coding results for both Intel and AMD, let's relax
the checks to simplify the test while supporting both implementations.
Note that:

• If a new hardware implementation comes up in the future, it is likely to pass the relaxed tests, i.e. no future maintenance burden for us.
• If something terribly wrong happens (e.g. instead of rsqrt we execute 1/sqrt), the tests will probably catch it, since the relaxed tests expect low precision (e.g. rsqrt(1) != 1.0).

[aartbik]

Welcome back old friend!

mlir/test/Integration/Dialect/Vector/CPU/X86Vector/test-rsqrt.mlir

 // RUN: mlir-opt %s -convert-vector-to-llvm="enable-x86vector" -convert-std-to-llvm | \
 // RUN: mlir-translate --mlir-to-llvmir | \
 // RUN: %lli --entry-function=entry --mattr="avx" --dlopen=%mlir_integration_test_dir/libmlir_c_runner_utils%shlibext | \
 // RUN: FileCheck %s
 
 func @entry() -> i32 {
   %i0 = constant 0 : i32
 
   %v = std.constant dense<[0.125, 0.25, 0.5, 1.0, 2.0, 4.0, 8.0, 16.0]> : vector<8xf32>
   %r = x86vector.avx.rsqrt %v : vector<8xf32>
   // `rsqrt` may produce slightly different results on Intel and AMD machines: accept both results here.
-  // CHECK: {{( 2.82764, 1.99951, 1.41382, 0.999756, 0.706909, 0.499878, 0.353455, 0.249939 | 2.82812, 1.99976, 1.41406, 0.999878, 0.707031, 0.499939, 0.353516, 0.249969 )}}
+  // CHECK: {{( 2.82[0-9]*, 1.99[0-9]*, 1.41[0-9]*, 0.99[0-9]*, 0.70[0-9]*, 0.49[0-9]*, 0.35[0-9]*, 0.24[0-9]* )}}
   vector.print %r : vector<8xf32>
 
   return %i0 : i32
 }