drm/msm/mdp4: Add error handling in mdp4_lvds_connector_init()

This patch adds error-handling for the drm_connector_init() and
drm_connector_attach_encoder inside the mdp4_lvds_connector_init().

Signed-off-by: liuhaoran <liuhaoran14@163.com>
---
 .../gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c    | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

Hi liuhaoran,

kernel test robot noticed the following build warnings:

[auto build test WARNING on drm-misc/drm-misc-next]
[also build test WARNING on linus/master v6.6-rc2 next-20230921]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/liuhaoran/drm-msm-mdp4-Add-error-handling-in-mdp4_lvds_connector_init/20230924-144326
base:   git://anongit.freedesktop.org/drm/drm-misc drm-misc-next
patch link:    https://lore.kernel.org/r/20230924064159.14739-1-liuhaoran14%40163.com
patch subject: [PATCH] drm/msm/mdp4: Add error handling in mdp4_lvds_connector_init()
config: arm-defconfig (https://download.01.org/0day-ci/archive/20230924/202309241619.RHCRkWza-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230924/202309241619.RHCRkWza-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202309241619.RHCRkWza-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c: In function 'mdp4_lvds_connector_init':
>> drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c:114:24: warning: returning 'int' from a function with return type 'struct drm_connector *' makes pointer from integer without a cast [-Wint-conversion]
     114 |                 return ret;
         |                        ^~~
   drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c:126:24: warning: returning 'int' from a function with return type 'struct drm_connector *' makes pointer from integer without a cast [-Wint-conversion]
     126 |                 return ret;
         |                        ^~~


vim +114 drivers/gpu/drm/msm/disp/mdp4/mdp4_lvds_connector.c

    92	
    93	/* initialize connector */
    94	struct drm_connector *mdp4_lvds_connector_init(struct drm_device *dev,
    95			struct device_node *panel_node, struct drm_encoder *encoder)
    96	{
    97		struct drm_connector *connector = NULL;
    98		struct mdp4_lvds_connector *mdp4_lvds_connector;
    99		int ret;
   100	
   101		mdp4_lvds_connector = kzalloc(sizeof(*mdp4_lvds_connector), GFP_KERNEL);
   102		if (!mdp4_lvds_connector)
   103			return ERR_PTR(-ENOMEM);
   104	
   105		mdp4_lvds_connector->encoder = encoder;
   106		mdp4_lvds_connector->panel_node = panel_node;
   107	
   108		connector = &mdp4_lvds_connector->base;
   109	
   110		ret = drm_connector_init(dev, connector, &mdp4_lvds_connector_funcs,
   111					 DRM_MODE_CONNECTOR_LVDS);
   112	
   113		if (ret)
 > 114			return ret;