drm/i915/dmc_wl: Track pipe interrupt registers

Pipe interrupt registers live in their respective pipes' power wells,
which are below PG0. That means that they must also be tracked as
registers that are powered-off during dynamic DC states.

There are probably more ranges that we need to track down and add to the
powered_off_ranges. However, let's make this change only about pipe
interrupt registers to fix some vblank timeouts observed due to the DMC
wakelock not being taken for those registers.

In the future, we might want to replace powered_off_ranges with a new
table to represent registers in PG0, which should be probably easier to
maintain. Any register not belonging to that table should be considered
powered off during dynamic DC states and, as such, requiring the DMC
wakelock for access.

Bspec: 72519, 71583
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Gustavo Sousa <gustavo.sousa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250113204306.112266-4-gustavo.sousa@intel.com