AK: Remove `kfree` definition

AK/Demangle.h

@@ -20,7 +20,7 @@ inline String demangle(StringView name)
     auto* demangled_name = abi::__cxa_demangle(name.to_string().characters(), nullptr, nullptr, &status);
     auto string = String(status == 0 ? demangled_name : name);
     if (status == 0)
-        kfree(demangled_name);
+        free(demangled_name);
     return string;
 }
 

AK/kmalloc.h

@@ -17,11 +17,10 @@
 
 #    define kmalloc malloc
 #    define kmalloc_good_size malloc_good_size
-#    define kfree free
 
 inline void kfree_sized(void* ptr, size_t)
 {
-    kfree(ptr);
+    free(ptr);
 }
 #endif