[mlir] Bump building CRunnerUtils from C++11 to C++17

[brad]

Summary

After https://reviews.llvm.org/D130025 I noticed I could not build CRunnerUtils on OpenBSD. But aligned_alloc() was not introduced until C++17. Since the rest of the tree has switch to C++17 then might as well do so here as well

[nikic]

LGTM

mlir/lib/ExecutionEngine/CMakeLists.txt

 add_mlir_library(mlir_c_runner_utils
   SHARED
   CRunnerUtils.cpp
   Float16bits.cpp
   SparseTensorUtils.cpp
 
   EXCLUDE_FROM_LIBMLIR
   )
-set_property(TARGET mlir_c_runner_utils PROPERTY CXX_STANDARD 11)
+set_property(TARGET mlir_c_runner_utils PROPERTY CXX_STANDARD 17)
 target_compile_definitions(mlir_c_runner_utils PRIVATE mlir_c_runner_utils_EXPORTS)
 
 add_mlir_library(mlir_runner_utils
   SHARED
   RunnerUtils.cpp
 
   EXCLUDE_FROM_LIBMLIR
 )