hw: explicitly include qemu/log.h

Move the inclusion out of hw/hw.h, most files do not need it.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/hw/gpio/pl061.c b/hw/gpio/pl061.c
index 29dc7fc..44faeb2 100644
--- a/hw/gpio/pl061.c
+++ b/hw/gpio/pl061.c
@@ -10,6 +10,7 @@
 
 #include "qemu/osdep.h"
 #include "hw/sysbus.h"
+#include "qemu/log.h"
 
 //#define DEBUG_PL061 1