accel/tcg: Store some tlb flags in CPUTLBEntryFull

We have run out of bits we can use within the CPUTLBEntry comparators,
as TLB_FLAGS_MASK cannot overlap alignment.

Store slow_flags[] in CPUTLBEntryFull, and merge with the flags from
the comparator.  A new TLB_FORCE_SLOW bit is set within the comparator
as an indication that the slow path must be used.

Move TLB_BSWAP to TLB_SLOW_FLAGS_MASK.  Since we are out of bits,
we cannot create a new bit without moving an old one.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>