migration/ram: Fix some helper functions' parameter to use PageSearchStatus

migration/ram: Fix some helper functions' parameter to use PageSearchStatus

Some helper functions use parameters 'RAMBlock *block' and 'ram_addr_t *offset',
We can use 'PageSearchStatus *pss' directly instead, with this change, we
can reduce the number of parameters for these helper function, also
it is easily to add new parameters for these helper functions.

Signed-off-by: zhanghailiang <zhang.zhanghailiang@huawei.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1452829066-9764-5-git-send-email-zhang.zhanghailiang@huawei.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>