fixed bug in inventory textures caused from better handling of unknown blocks

src/mapnode.cpp

@@ -146,7 +146,6 @@ void init_mapnode()
 	{
 		ContentFeatures *f = &g_content_features[i];
 		f->setAllTextures("unknown_block.png");
-		f->setInventoryTextureCube("unknown_block.png", "unknown_block.png", "unknown_block.png");
 		f->dug_item = std::string("MaterialItem ")+itos(i)+" 1";
 	}
 

src/mapnode.h

@@ -194,6 +194,8 @@ struct ContentFeatures
 		{
 			setTexture(i, name, alpha);
 		}
+		// Force inventory texture too
+		setInventoryTexture(name);
 	}
 
 	void setTile(u16 i, const TileSpec &tile)