driver: soc: xilinx: fix memory leak in xlnx_add_cb_for_notify_event()

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: driver: soc: xilinx: fix memory leak in xlnx_add_cb_for_notify_event() The kfree() should be called when memory fails to be allocated for cb_data in xlnx_add_cb_for_notify_event(), otherwise there will be a memory leak, so add kfree() to fix it.

References

• https://git.kernel.org/stable/c/d35290addcbac94b076babe0a798a8c043421812
• https://git.kernel.org/stable/c/9dfb6c784e385f6e61994bb4e16ce12f3e4940be
• https://git.kernel.org/stable/c/1bea534991b9b35c41848a397666ada436456beb