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: 3a4bfa09 ("drm/i915/selftest: Fix workarounds selftest for GuC submission")
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Rahul Kumar Singh <rahul.kumar.singh@intel.com>
Cc: John Harrison <John.C.Harrison@Intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240222113347.648945-2-janusz.krzysztofik@linux.intel.com


(cherry picked from commit 6ee3f54b)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>