PR libstdc++/83607
	* include/std/functional (__is_byte_like): New trait.
	(__is_std_equal_to): Remove.
	(__boyer_moore_base_t): Use __is_byte_like instead of
	__is_std_equal_to.
	* include/experimental/functional (__is_std_equal_to): Remove.
	(__boyer_moore_base_t): Use __is_byte_like instead of
	__is_std_equal_to.
	* testsuite/20_util/function_objects/83607.cc: New test.

From-SVN: r256231