Setting the IMOD value below 0x3F8 can cause IRQ lockups in the Intel
LynxPoint USB 3.0 controllers found in MacBookPro 2013's.

MFC after:	2 days
Tested by:	Huang Wen Hui <huanghwh@gmail.com>
Finish connecting up installer UEFI support. If the kernel was booted using
EFI, set up the disks for an EFI system. If booted from BIOS/CSM, set up
for BIOS.