drm/bridge: tc358764: Fix build error

If CONFIG_DRM_TOSHIBA_TC358764=y but CONFIG_DRM_KMS_HELPER=m,
building fails:

drivers/gpu/drm/bridge/tc358764.o:(.rodata+0x228): undefined reference to `drm_atomic_helper_connector_reset'
drivers/gpu/drm/bridge/tc358764.o:(.rodata+0x240): undefined reference to `drm_helper_probe_single_connector_modes'
drivers/gpu/drm/bridge/tc358764.o:(.rodata+0x268): undefined reference to `drm_atomic_helper_connector_duplicate_state'
drivers/gpu/drm/bridge/tc358764.o:(.rodata+0x270): undefined reference to `drm_atomic_helper_connector_destroy_state'

Like TC358767, select DRM_KMS_HELPER to fix this, and
change to select DRM_PANEL to avoid recursive dependency.

Reported-by: Hulk Robot <hulkci@huawei.com>
Fixes: f38b7cca

 ("drm/bridge: tc358764: Add DSI to LVDS bridge driver")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Neil Armstrong <narmstrong@baylibre.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190729090520.25968-1-yuehaibing@huawei.com