qemu: endjob returns a bool

qemu: endjob returns a bool

Osier Yang pointed out that ever since commit 31cb030, the
signature of qemuDomainObjEndJob was changed to return a bool.
While comparison against 0 or > 0 still gives the right results,
it looks fishy; we also had one place that was comparing < 0
which is effectively dead code.

* src/qemu/qemu_migration.c (qemuMigrationPrepareAny): Fix dead
code bug.
(qemuMigrationBegin): Use more canonical form of bool check.
* src/qemu/qemu_driver.c (qemuAutostartDomain)
(qemuDomainCreateXML, qemuDomainSuspend, qemuDomainResume)
(qemuDomainShutdownFlags, qemuDomainReboot, qemuDomainReset)
(qemuDomainDestroyFlags, qemuDomainSetMemoryFlags)
(qemuDomainSetMemoryStatsPeriod, qemuDomainInjectNMI)
(qemuDomainSendKey, qemuDomainGetInfo, qemuDomainScreenshot)
(qemuDomainSetVcpusFlags, qemuDomainGetVcpusFlags)
(qemuDomainRestoreFlags, qemuDomainGetXMLDesc)
(qemuDomainCreateWithFlags, qemuDomainAttachDeviceFlags)
(qemuDomainUpdateDeviceFlags, qemuDomainDetachDeviceFlags)
(qemuDomainBlockResize, qemuDomainBlockStats)
(qemuDomainBlockStatsFlags, qemuDomainMemoryStats)
(qemuDomainMemoryPeek, qemuDomainGetBlockInfo)
(qemuDomainAbortJob, qemuDomainMigrateSetMaxDowntime)
(qemuDomainMigrateGetCompressionCache)
(qemuDomainMigrateSetCompressionCache)
(qemuDomainMigrateSetMaxSpeed)
(qemuDomainSnapshotCreateActiveInternal)
(qemuDomainRevertToSnapshot, qemuDomainSnapshotDelete)
(qemuDomainQemuMonitorCommand, qemuDomainQemuAttach)
(qemuDomainBlockJobImpl, qemuDomainBlockCopy)
(qemuDomainBlockCommit, qemuDomainOpenGraphics)
(qemuDomainGetBlockIoTune, qemuDomainGetDiskErrors)
(qemuDomainPMSuspendForDuration, qemuDomainPMWakeup)
(qemuDomainQemuAgentCommand, qemuDomainFSTrim): Likewise.

Signed-off-by: Eric Blake <eblake@redhat.com>
(cherry picked from commit 6cd15482586334a822d248dd8b94cee0635d3e64)

Conflicts:
	src/qemu/qemu_driver.c - some intermediate patches not backported