drm/i915/fbc: drop uncore locking around i8xx/i965 fbc nuke

The locking should not be needed after commits de5bd083
("drm/i915/fbc: Skip nuke when flip is pending") and 7cfd1a18
("drm/i915: Remove remaining locks from i9xx plane udpates").

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: NJani Nikula <jani.nikula@intel.com>
Reviewed-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221205122918.3092092-1-jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_fbc.c

@@ -323,10 +323,8 @@ static void i8xx_fbc_nuke(struct intel_fbc *fbc)
 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
 	struct drm_i915_private *dev_priv = fbc->i915;
 
-	spin_lock_irq(&dev_priv->uncore.lock);
 	intel_de_write_fw(dev_priv, DSPADDR(i9xx_plane),
 			  intel_de_read_fw(dev_priv, DSPADDR(i9xx_plane)));
-	spin_unlock_irq(&dev_priv->uncore.lock);
 }
 
 static void i8xx_fbc_program_cfb(struct intel_fbc *fbc)
@@ -359,10 +357,8 @@ static void i965_fbc_nuke(struct intel_fbc *fbc)
 	enum i9xx_plane_id i9xx_plane = fbc_state->plane->i9xx_plane;
 	struct drm_i915_private *dev_priv = fbc->i915;
 
-	spin_lock_irq(&dev_priv->uncore.lock);
 	intel_de_write_fw(dev_priv, DSPSURF(i9xx_plane),
 			  intel_de_read_fw(dev_priv, DSPSURF(i9xx_plane)));
-	spin_unlock_irq(&dev_priv->uncore.lock);
 }
 
 static const struct intel_fbc_funcs i965_fbc_funcs = {