sw64: iommu: fix the mask of physical address when flushing pcache

Sunway inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I6ILC2

--------------------------------

PCACHE_FLUSHPADDR reg specifies addr[47:7] of the physical address
of the pte to be flushed, and other bits reserved, so we can write
the physical address directly into the reg.
Signed-off-by: NZheng Chongzhen <zhengchongzhen@wxiat.com>
Reviewed-by: NHe Sheng <hesheng@wxiat.com>
Signed-off-by: NGu Zitao <guzitao@wxiat.com>

drivers/iommu/sw64/sunway_iommu.c

@@ -167,7 +167,7 @@ flush_device_tlb(struct sunway_iommu_domain *sdomain,
 
 	switch (hflush_addr) {
 	case PCACHE_FLUSHPADDR:
-		flush_addr = __pa(flush_addr) & 0xffffffff80;
+		flush_addr = __pa(flush_addr);
 		/* Set memory bar here */
 		mb();
 		write_piu_ior0(hose->node, hose->index,