This change limits fault injection to general-purpose registers, instead of
relying on the LLVM/Fail* bridge to only recognize the status register
(EFLAGS on x86) and general-purpose registers. Since this bridge just
learned to translate x86's control and segment registers, and these
registers need special handling for fault injection (def/use pruning does
not work here), only import register accesses from the RT_GP subset.
Status register and instruction pointer injection remain functional, and
import-trace now should work architecture independently.
Change-Id: Id8ad2f0a9dab1861bf16ea9443c3bdfe7213d3fa
84a03b55ff