power: sequencing: thead-gpu: use new defines for match() return values

Replace the magic numbers with proper defines we now have in the header.

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Link: https://lore.kernel.org/r/20250624-pwrseq-match-defines-v1-5-a59d90a951f1@linaro.org


Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>