VMware: Fix bug for root disk size

The code would not configure the root disk size to that specified
in the flavor. This was always the size of the glance image.

Fixes bug: 1226052

(cherry picked from commit f0a9b31d90532dd278c12572767c3874648dcaec)

Conflicts:

	nova/tests/virt/vmwareapi/test_vmwareapi.py
	nova/virt/vmwareapi/vmops.py

Change-Id: Ifc41e6f5bf95c17bac6ab26e9c08aa28d0325bcd
Merge "VMware: Fix bug for root disk size" into stable/grizzly