qdev: Use returned bool to check for qdev_realize() etc. failure

Convert

    foo(..., &err);
    if (err) {
        ...
    }

to

    if (!foo(..., &err)) {
        ...
    }

for qdev_realize(), qdev_realize_and_unref(), qbus_realize() and their
wrappers isa_realize_and_unref(), pci_realize_and_unref(),
sysbus_realize(), sysbus_realize_and_unref(), usb_realize_and_unref().
Coccinelle script:

    @@
    identifier fun = {
        isa_realize_and_unref, pci_realize_and_unref, qbus_realize,
        qdev_realize, qdev_realize_and_unref, sysbus_realize,
        sysbus_realize_and_unref, usb_realize_and_unref
    };
    expression list args, args2;
    typedef Error;
    Error *err;
    @@
    -    fun(args, &err, args2);
    -    if (err)
    +    if (!fun(args, &err, args2))
         {
             ...
         }

Chokes on hw/arm/musicpal.c's lcd_refresh() with the unhelpful error
message "no position information".  Nothing to convert there; skipped.

Fails to convert hw/arm/armsse.c, because Coccinelle gets confused by
ARMSSE being used both as typedef and function-like macro there.
Converted manually.

A few line breaks tidied up manually.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <20200707160613.848843-5-armbru@redhat.com>

2 files changed, 2 insertions, 4 deletions

diff --git a/hw/block/fdc.c b/hw/block/fdc.c
index 3425d56e2a..3be8c7be5b 100644
--- a/hw/block/fdc.c
+++ b/hw/block/fdc.c
@@ -2575,8 +2575,7 @@ static void fdctrl_connect_drives(FDCtrl *fdctrl, DeviceState *fdc_dev,
             return;
         }
 
-        qdev_realize_and_unref(dev, &fdctrl->bus.bus, &local_err);
-        if (local_err) {
+        if (!qdev_realize_and_unref(dev, &fdctrl->bus.bus, &local_err)) {
             error_propagate(errp, local_err);
             return;
         }
diff --git a/hw/block/xen-block.c b/hw/block/xen-block.c
index 1b7bc5de08..10c44dfda2 100644
--- a/hw/block/xen-block.c
+++ b/hw/block/xen-block.c
@@ -961,8 +961,7 @@ static void xen_block_device_create(XenBackendInstance *backend,
     blockdev->iothread = iothread;
     blockdev->drive = drive;
 
-    qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), &local_err);
-    if (local_err) {
+    if (!qdev_realize_and_unref(DEVICE(xendev), BUS(xenbus), &local_err)) {
         error_propagate_prepend(errp, local_err,
                                 "realization of device %s failed: ",
                                 type);