drm/i915: Name structure in dev_priv that contains RPS/RC6 state as "gt_pm"

drm/i915: Name structure in dev_priv that contains RPS/RC6 state as "gt_pm"

Prepared substructure rps for RPS related state. autoenable_work is
used for RC6 too hence it is defined outside rps structure. As we do
this lot many functions are refactored to use intel_rps *rps to access
rps related members. Hence renamed intel_rps_client pointer variables
to rps_client in various functions.

v2: Rebase.

v3: s/pm/gt_pm (Chris)
Refactored access to rps structure by declaring struct intel_rps * in
many functions.

Signed-off-by: Sagar Arun Kamble <[email protected]>
Cc: Chris Wilson <[email protected]>
Cc: Imre Deak <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Reviewed-by: Radoslaw Szwichtenberg <[email protected]> #1
Reviewed-by: Chris Wilson <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
Acked-by: Imre Deak <[email protected]>
Signed-off-by: Chris Wilson <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]