fix missing #define when UNIT_EXCLUDE_FLOAT is used

src/unity.c

@@ -32,12 +32,14 @@ const char* UnityStrInf      = "Infinity";
 const char* UnityStrNegInf   = "Negative Infinity";
 const char* UnityStrNaN      = "NaN";
 
+#ifndef UNITY_EXCLUDE_FLOAT
 // Dividing by these constants produces +/- infinity.
 // The rationale is given in UnityAssertFloatIsInf's body.
 static const _UF f_zero = 0.0f;
 #ifndef UNITY_EXCLUDE_DOUBLE
 static const _UD d_zero = 0.0;
 #endif
+#endif
 
 // compiler-generic print formatting masks
 const _U_UINT UnitySizeMask[] =