Simulate TF32 with BF16x3 (#3142)

* tf32:bf16x3:use bf16x3 emulate tf32 gemm

* change blockwiseGemm to demo bf16x3

* temp push

* self review

* self review

* fix multi-device compile error

* bug fix

* code refactor

* limit to gfx950

* enhance gemm gfx942 threshold

* lower change from blockwise to warpwise

* refact codes

* refact codes

* error fix

* change threshold

* bug fix

* fix threshold error

* change host reference implement to same as device

* bug fix

* bug fix

* code refact

* fix clang-format fail

* code refine

include/ck/library/utility/check_err.hpp

@@ -168,8 +168,8 @@ typename std::enable_if<
 check_err(const Range& out,
           const RefRange& ref,
           const std::string& msg = "Error: Incorrect results!",
-          double rtol            = 1e-5,
-          double atol            = 3e-5)
+          double rtol            = 5e-4,
+          double atol            = 5e-4)
 {
     if(out.size() != ref.size())
     {