target/arm: Convert init_cpreg_list to g_hash_table_foreach

target/arm: Convert init_cpreg_list to g_hash_table_foreach

Adjust count_cpreg and add_cpreg_to_list to be used with
g_hash_table_foreach instead of g_list_foreach.  In this way we have
the ARMCPRegInfo pointer directly rather than having to look it up
from the key.

Delay the sorting of the cpreg_indexes until after add_cpreg_to_list.
This allows us to sort the data that we actually care about,
the kvm id, as computed within add_cpreg_to_list, instead of
having to repeatedly compute the kvm id within cpreg_key_compare.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>