drm/xe: Fix bug in idledly unit conversion

drm/xe: Fix bug in idledly unit conversion

We only need to convert to picosecond units before writing to RING_IDLEDLY.

Fixes: 7c53ff050ba8 ("drm/xe: Apply Wa_16023105232")
Cc: Tangudu Tilak Tirumalesh <tilak.tirumalesh.tangudu@intel.com>
Acked-by: Tangudu Tilak Tirumalesh <tilak.tirumalesh.tangudu@intel.com>
Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar@intel.com>
Link: https://patch.msgid.link/20260401012710.4165547-1-vinay.belgaumkar@intel.com
(cherry picked from commit 13743bd628bc9d9a0e2fe53488b2891aedf7cc74)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>