tenderloin: Clean up unused regulator code

Change-Id: I0b67436d8fbec219bd0ffcec32d8ff75ad092cfa
acpuclock-8x60:  support 64 bit

was added in a while back but 8x60 missed out

Change-Id: I4dbbaf870a7867e51a90d2dac6411936cd11a2a2