IS_ONE_OF macro to make long chains of conditions more concise and easy to follow (#4860)

* Is one of macro

* Moar

* Whoops

* Trunk

* isOneOf function backed macro

src/meshUtils.cpp

@@ -80,4 +80,19 @@ bool memfll(const uint8_t *mem, uint8_t find, size_t numbytes)
             return false;
     }
     return true;
+}
+
+bool isOneOf(int item, int count, ...)
+{
+    va_list args;
+    va_start(args, count);
+    bool found = false;
+    for (int i = 0; i < count; ++i) {
+        if (item == va_arg(args, int)) {
+            found = true;
+            break;
+        }
+    }
+    va_end(args);
+    return found;
 }