Revert "X86 platform: New BayTrail IOSF-SB MBI driver"

This reverts commit 997ab407d2b4e7d7ce2788d2de68435eb94fcfec. This driver is
replaced by the more general SOC IOSF driver in commit 46184415368a.

Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Matthew Garrett <matthew.garrett@nebula.com>

diff --cc drivers/platform/x86/Kconfig
Simple merge

diff --cc drivers/platform/x86/Makefile
Simple merge

diff --cc drivers/platform/x86/intel_baytrail.c
Simple merge

diff --cc drivers/platform/x86/intel_baytrail.h
Simple merge