The various bit string instructions (bts, btc, etc.) fail to adjust the
address correctly if the bit address is beyond BITS_PER_LONG.

This bug creeped in as the emulator originally relied on cr2 to contain the
memory address; however we now decode it from the mod r/m bits, and must
adjust the offset to account for large bit indices.

The patch is rather large because it switches src and dst decoding around, so
that the bit index is available when decoding the memory address.

This fixes workloads like the FC5 installer.
Signed-off-by: Avi Kivity <avi@qumranet.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>