ARM64: zynqmp: pm: Fix memory leak

ARM64: zynqmp: pm: Fix memory leak

There is a memory leak issue in the PM driver.
The function processing user input uses strsep on a kzalloc'd memory
pointer and later kfrees the same pointer.
Since every strsep call modifies the string pointer, it eventually
points to NULL, thereby passing a NULL pointer to kfree, thus causing a
leak.
The solution is to copy the address of kzalloc'd memory in another
pointer, and kfree this instead.

Reported-by: Rohit Fule <rohit.fule@gmail.com>
Signed-off-by: Soren Brinkmann <soren.brinkmann@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>