Intermittently it is found that when multiple SATA disks are directly
connected to the host that some disks are not detected.  The problem is
that all set bitfields in ENT_INT_SRC1 are cleared for all phys in
sata_int_v2_hw() - it should clear the set bit for the phy being
serviced.

Also unnecessary double-write to ENT_INT_SRC1 and ENT_INT_SRC_MSK1 is
removed (remaining writes are done at end label).
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>