VMware: remove Host class

The class was only used by the ESX driver which was remove in the
commit 1deb31f85a8f5d1e261b2cf1eddc537a5da7f60b.

Change-Id: I026e4c0f463e78e33592c6408d2e688c74a0714b
VMware: remove specific VC support from class VMwareVolumeOps

This support is no longer needed as we only support the VC driver
since commit 1deb31f85a8f5d1e261b2cf1eddc537a5da7f60b.

Change-Id: Iad71fceb580620b1843ce3cf5d926343d8113945
Merge "VMware: remove Host class"
Merge "VMware: remove specific VC support from class VMwareVolumeOps"