qga: fix w32 breakage due to missing osdep.h includes

requester.h relied on qemu/compiler.h definitions to
handle GCC_FMT_ATTR() stub, but this include was removed as part
of scripted clean-ups via 30456d5:

  all: Clean up includes

under the assumption that all C files would have included it via
qemu/osdep.h at that point. requester.cpp was likely missed
due to C++ files requiring manual/special handling as well as
VSS build options needing to be enabled to trigger build failures.

Fix this by including qemu/osdep.h. That in turn pulls in a
macro from qapi/error.h that conflicts with a struct field name
in requester.h, so fix that as well by renaming the field.

While we're at it, fix up provider.cpp/install.cpp to include
osdep.h as well.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Reviewed-by: Eric Blake <eblake@redhat.com>

qga/vss-win32/requester.cpp

@@ -10,7 +10,7 @@
  * See the COPYING file in the top-level directory.
  */
 
-#include <stdio.h>
+#include "qemu/osdep.h"
 #include "vss-common.h"
 #include "requester.h"
 #include "assert.h"
@@ -23,9 +23,9 @@
 /* Call QueryStatus every 10 ms while waiting for frozen event */
 #define VSS_TIMEOUT_EVENT_MSEC 10
 
-#define err_set(e, err, fmt, ...)                                       \
-    ((e)->error_setg_win32((e)->errp, __FILE__, __LINE__, __func__,     \
-                           err, fmt, ## __VA_ARGS__))
+#define err_set(e, err, fmt, ...)                                           \
+    ((e)->error_setg_win32_wrapper((e)->errp, __FILE__, __LINE__, __func__, \
+                                   err, fmt, ## __VA_ARGS__))
 /* Bad idea, works only when (e)->errp != NULL: */
 #define err_is_set(e) ((e)->errp && *(e)->errp)
 /* To lift this restriction, error_propagate(), like we do in QEMU code */