In 7.1i XPower, VCCIO power estimate figures are not being reported for CoolRunner-II device flow; only core power is being reported. This is a bug specifically affecting designs that target CoolRunner-II parts. This is not the case for FPGA targets.
The issue is scheduled to be fixed in 9.1i.
Until this bug is fixed, an alternative that can be used in order to estimate power on VCCIO is using the following formula:
Power = # of outputs x frequency (in MHz) x (0.01 + external capacitance load in uF) x VCCIO x VCCIO
So, for 10 outputs at 100 MHz at LVCMOS25 would be with a 5pF (= 0.005 uF) external load 10 x 100 x (0.01+0.005) x 2.5 x 2.5 = 93.75 mW.