drm/edid: fixed the bug that hdr metadata was not reset

drm/edid: fixed the bug that hdr metadata was not reset

When DP connected to a device with HDR capability,
the hdr structure was filled.Then connected to another
sink device without hdr capability, but the hdr info
still exist.

Fixes: e85959d6cbe0 ("drm: Parse HDR metadata info from EDID")
Cc: <stable@vger.kernel.org> # v5.3+
Signed-off-by: "feijuan.li" <feijuan.li@samsung.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Link: https://lore.kernel.org/r/20250514063511.4151780-1-feijuan.li@samsung.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>