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

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: 4446fcf220ce ("drm/xe/hwmon: Expose power1_max_interval")
Signed-off-by: Karthik Poosa <[email protected]>
Reviewed-by: Anshuman Gupta <[email protected]>
Cc: Badal Nilawar <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Signed-off-by: Lucas De Marchi <[email protected]>