BUG: EGI coords read but not transformed

[larsoner]

Doing:

mne.viz.plot_alignment(mne.io.read_raw_egi('test_egi.mff').info, show_axes=True, dig=True, eeg=True, coord_frame='head')

gets sensor positions plus LPA/Nasion/RPA (good), but not transformed to the head coordinate frame (bad):