w32: Fix missing declaration of ffs()

target-ppc/cpu.h now needs ffs(), too, so ffs() must be declared
before this file is included.

Moving the declaration from qemu-common.h to qemu-os-win32.h
(which is included in qemu-common.h early) fixes the compiler
warning for w32.

Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>

qemu-common.h

@@ -201,11 +201,6 @@ const char *path(const char *pathname);
 #define qemu_isascii(c)		isascii((unsigned char)(c))
 #define qemu_toascii(c)		toascii((unsigned char)(c))
 
-#ifdef _WIN32
-/* ffs() in oslib-win32.c for WIN32, strings.h for the rest of the world */
-int ffs(int i);
-#endif
-
 void *qemu_oom_check(void *ptr);
 void *qemu_malloc(size_t size);
 void *qemu_realloc(void *ptr, size_t size);

qemu-os-win32.h

@@ -29,6 +29,9 @@
 #include <windows.h>
 #include <winsock2.h>
 
+/* Declaration of ffs() is missing in MinGW's strings.h. */
+int ffs(int i);
+
 /* Polling handling */
 
 /* return TRUE if no sleep should be done afterwards */