drm/xe/guc: Limit sleep while waiting for H2G credits

drm/xe/guc: Limit sleep while waiting for H2G credits

Instead of endlessly increasing the sleep timeout while waiting
for the H2G credits, use exponential increase only up to the given
limit, like it was initially done in the GuC submission code.

While here, fix the actual timeout to the 1s as it was documented.

Suggested-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patch.msgid.link/20260127193727.601-4-michal.wajdeczko@intel.com