fixed typo

lib/single-file/single-file-core.js

@@ -292,7 +292,7 @@ this.SingleFileCore = (() => {
 				if (srcset && imgElement.srcset != srcset) {
 					imgElement.srcset = srcset;
 					imgElement.removeAttribute("data-srcset");
-					element.removeAttribute("data-lazyload");
+					imgElement.removeAttribute("data-lazyload");
 				}
 			});
 		}