drm/i915/selftests: Fix dependency of some timeouts on HZ

drm/i915/selftests: Fix dependency of some timeouts on HZ

Third argument of i915_request_wait() accepts a timeout value in jiffies.
Most users pass either a simple HZ based expression, or a result of
msecs_to_jiffies(), or MAX_SCHEDULE_TIMEOUT, or a very small number not
exceeding 4 if applicable as that value.  However, there is one user --
intel_selftest_wait_for_rq() -- that passes a WAIT_FOR_RESET_TIME symbol,
defined as a large constant value that most probably represents a desired
timeout in ms.  While that usage results in the intended value of timeout
on usual x86_64 kernel configurations, it is not portable across different
architectures and custom kernel configs.

Rename the symbol to clearly indicate intended units and convert it to
jiffies before use.

Fixes: 3a4bfa091c46 ("drm/i915/selftest: Fix workarounds selftest for GuC submission")
Signed-off-by: Janusz Krzysztofik <[email protected]>
Cc: Rahul Kumar Singh <[email protected]>
Cc: John Harrison <[email protected]>
Cc: Matthew Brost <[email protected]>
Reviewed-by: Andi Shyti <[email protected]>
Signed-off-by: Andi Shyti <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]
(cherry picked from commit 6ee3f54b880c91ab2e244eb4ffd4bfed37832b25)
Signed-off-by: Joonas Lahtinen <[email protected]>