drm/amd/display: off by one in find_irq_source_info()

The ->info[] array has DAL_IRQ_SOURCES_NUMBER elements so this condition
should be >= instead of > or we could read one element beyond the end of
the array.

Fixes: 4562236b ("drm/amd/dc: Add dc display driver (v2)")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>