drm/xe/hwmon: Cast result to output precision on left shift of operand

Address potential overflow in result of left shift of a
lower precision (u32) operand before assignment to higher
precision (u64) variable.

v2:
 - Update commit message. (Himal)

Fixes: 4446fcf2

 ("drm/xe/hwmon: Expose power1_max_interval")
Signed-off-by: Karthik Poosa <karthik.poosa@intel.com>
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
Cc: Badal Nilawar <badal.nilawar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240405130127.1392426-5-karthik.poosa@intel.com
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
(cherry picked from commit 883232b4

)
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>