drm/xe/client: bo->client does not need bos_lock

drm/xe/client: bo->client does not need bos_lock

bos_lock is to protect list of bos used by client, it is
not required to protect bo->client so bring it outside of
bos_lock.

Fixes: b27970f3e11c ("drm/xe: Add tracking support for bos per client")
Signed-off-by: Tejas Upadhyay <tejas.upadhyay@intel.com>
Reviewed-by: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250205051042.1991192-1-tejas.upadhyay@intel.com
Signed-off-by: Nirmoy Das <nirmoy.das@intel.com>