Now that we have the prerequisites in target/hppa/,
implement the hardware for a PA7100LC.

This also enables build for hppa-softmmu.

Signed-off-by: Helge Deller <deller@gmx.de>
[rth: Since it is all new code, squashed all branch development
withing hw/hppa/ to a single patch.]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>