The regulator can take that, but as far as I can see it's only for DVDD, the core voltage of 1.1 V. You also need at least IOVDD, which should be between 1.8 V and 3.3 V. So you'll need to supply some lower voltage externally anyway.

I suppose the main draw of the regulator is that the DVDD rail will consume the most power. 1.1 V is also much more exotic than 3.3 V.