drm/i915: switch to use kernel standard error injection

drm/i915: switch to use kernel standard error injection

Switch error injection testing from i915_inject_probe_failure
to ALLOW_ERROR_INJECTION. Here taken out calls to
i915_inject_probe_failure and changed to use
ALLOW_ERROR_INJECTION for the same functions.

Below functions are dropped from testing since I
couldn't hit those at module bind time, testing
these would just fail the tests. To include these
in test would need to find way to cause resetting in i915
which would trigger these:

intel_gvt_init
intel_wopcm_init
intel_uc_fw_upload
intel_gt_init with expected -EIO (-EINVAL is tested)
lrc_init_wa_ctx
intel_huc_auth
guc_check_version_range
intel_uc_fw_fetch
uc_fw_xfer
__intel_uc_reset_hw
guc_enable_communication
uc_init_wopcm
..and all stages of __force_fw_fetch_failures

Signed-off-by: Juha-Pekka Heikkila <juhapekka.heikkila@gmail.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Link: https://patch.msgid.link/20251216080754.221974-2-juhapekka.heikkila@gmail.com