drm/i915/gt: Pass the -EINVAL when emit_pte doesn't update any PTE

When emit_pte doesn't update any PTE with return value as 0, interpret
it as -EINVAL.

v2:
  Add missing goto [Thomas]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Thomas Hellstrom <thomas.hellstrom@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220405150840.29351-5-ramalingam.c@intel.com