[][Kernel][hnat][FiX hnat coverity issue]

[Description]
Fix hnat coverity issue.
"Uninitialized scalar variable" in hnat_get_ppe_hash.
"Calling risky function" in hnat_xlat_cfg_write.
"Untrusted pointer read" in mtk_464xlat_pre_process

[Release-log]


Change-Id: I5f5158eba3b81ad40ed6b6ac86f1f38d973dee8a
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/7440578
2 files changed