If you want to avoid the semantic trouble of placing divs inside anchor tags, just place the anchor tag on the same level as the divs, wrap them all with a container with position: relative, make your anchor tag position: absolute and expand it to fill the container. Also if it's not on the end of the content flow make sure you throw a z-index in there to place it above the content.
As suggested I have added a markup code:
<div class="div__container>
<div class="div__one>
</div>
<div class="div__two">
</div>
<a href="#"></a>
</div>
And the css:
.div__container {
position: relative;
}
.div__container a {
position: absolute;
top: 0;
bottom: 0;
left: 0;
right: 0;
z-index: 999;
}