Remove isinf workaround

include/fmt/printf.h

@@ -16,6 +16,10 @@
 FMT_BEGIN_NAMESPACE
 namespace internal {
 
+// A helper function to suppress bogus "conditional expression is constant"
+// warnings.
+template <typename T> inline T const_check(T value) { return value; }
+
 // Checks if a value fits in int - used to avoid warnings about comparing
 // signed and unsigned integers.
 template <bool IsSigned> struct int_checker {