media: MAINTAINERS: ipu3-imgu: Add Tian Shu and Bingbu as reviewers

Add Bingbu Cao and Tian Shu Qiu as reviewers for the IPU3 ImgU driver.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Cc: Bingbu Cao <bingbu.cao@intel.com>
Cc: Tian Shu Qiu <tian.shu.qiu@intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

MAINTAINERS

@@ -8652,6 +8652,8 @@ F:	drivers/media/pci/intel/ipu3/
 
 INTEL IPU3 CSI-2 IMGU DRIVER
 M:	Sakari Ailus <sakari.ailus@linux.intel.com>
+R:	Bingbu Cao <bingbu.cao@intel.com>
+R:	Tian Shu Qiu <tian.shu.qiu@intel.com>
 L:	linux-media@vger.kernel.org
 S:	Maintained
 F:	Documentation/admin-guide/media/ipu3.rst