drm: move drv test macros out of drmP.h

Last bit the prevented us from starting to delete the drmP.h monster
includes from source files!

Also add kernel-doc while moving them.

A nice consistent drm_dev_ prefix would be cute for these, but since
they're used everywhere I've figured I'll leave this bikeshed aside
for now.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180709084016.23750-2-daniel.vetter@ffwll.ch

include/drm/drmP.h

@@ -102,25 +102,6 @@ struct pci_controller;
 #define DRM_SWITCH_POWER_CHANGING 2
 #define DRM_SWITCH_POWER_DYNAMIC_OFF 3
 
-static inline bool drm_core_check_feature(struct drm_device *dev, int feature)
-{
-	return dev->driver->driver_features & feature;
-}
-
-/**
- * drm_drv_uses_atomic_modeset - check if the driver implements
- * atomic_commit()
- * @dev: DRM device
- *
- * This check is useful if drivers do not have DRIVER_ATOMIC set but
- * have atomic modesetting internally implemented.
- */
-static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
-{
-	return drm_core_check_feature(dev, DRIVER_ATOMIC) ||
-		dev->mode_config.funcs->atomic_commit != NULL;
-}
-
 /* returns true if currently okay to sleep */
 static inline bool drm_can_sleep(void)
 {

include/drm/drm_drv.h

@@ -649,6 +649,35 @@ static inline bool drm_dev_is_unplugged(struct drm_device *dev)
 	return true;
 }
 
+/**
+ * drm_core_check_feature - check driver feature flags
+ * @dev: DRM device to check
+ * @feature: feature flag
+ *
+ * This checks @dev for driver features, see &drm_driver.driver_features and the
+ * various DRIVER_\* flags.
+ *
+ * Returns true if the @feature is supported, false otherwise.
+ */
+static inline bool drm_core_check_feature(struct drm_device *dev, int feature)
+{
+	return dev->driver->driver_features & feature;
+}
+
+/**
+ * drm_drv_uses_atomic_modeset - check if the driver implements
+ * atomic_commit()
+ * @dev: DRM device
+ *
+ * This check is useful if drivers do not have DRIVER_ATOMIC set but
+ * have atomic modesetting internally implemented.
+ */
+static inline bool drm_drv_uses_atomic_modeset(struct drm_device *dev)
+{
+	return drm_core_check_feature(dev, DRIVER_ATOMIC) ||
+		dev->mode_config.funcs->atomic_commit != NULL;
+}
+
 
 int drm_dev_set_unique(struct drm_device *dev, const char *name);