Change mbformat to mb_float_format in hypervisor table

In hypervisor table, if you have total of 3.8GB of memory,
it show 3GB. Need to change mbformat to mb_float_format.

Closes-bug:#1317817

Change-Id: I035e8002852994a2e3b426ce81667b9239ba06eb
Merge "Change mbformat to mb_float_format in hypervisor table"