drm/i915/bios: double check array-boundary in parse_sdvo_lvds_data

drm/i915/bios: double check array-boundary in parse_sdvo_lvds_data

During static analysis, a concern was raised that we may access the
dtd->dtd[] array out of bounds, because we are not checking whether
the index we use is larger than the array.

This should not be a problem as is, because the enumeration that is
used for this index comes from "panel_type", which uses an enumeration
with 4 items.  But if this enumeration is ever changed, it can lead to
hard-to-detect bugs, so better double-check it before using it as an
index to the array.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240528112901.476068-2-luciano.coelho@intel.com