log: Change log_cpu_state[_mask]() argument to CPUState

Since commit 878096eeb278a8ac1ccd6667af73e026f29b4cf5 (cpu: Turn
cpu_dump_{state,statistics}() into CPUState hooks) CPUArchState is no
longer needed.

Add documentation and make the functions available through qemu/log.h
outside NEED_CPU_H to allow use in qom/cpu.c. Moving them to qom/cpu.h
was not yet possible due to convoluted include paths, so that some
devices grow an implicit and unneeded dependency on qom/cpu.h for now.

Acked-by: Michael Walle <michael@walle.cc> (for lm32)
Reviewed-by: Richard Henderson <rth@twiddle.net>
[AF: Simplified mb_cpu_do_interrupt() and do_interrupt_all() changes]
Signed-off-by: Andreas Färber <afaerber@suse.de>
diff --git a/exec.c b/exec.c
index 61b094a..f01e3b6 100644
--- a/exec.c
+++ b/exec.c
@@ -617,7 +617,7 @@
         qemu_log("qemu: fatal: ");
         qemu_log_vprintf(fmt, ap2);
         qemu_log("\n");
-        log_cpu_state(env, CPU_DUMP_FPU | CPU_DUMP_CCOP);
+        log_cpu_state(cpu, CPU_DUMP_FPU | CPU_DUMP_CCOP);
         qemu_log_flush();
         qemu_log_close();
     }