kprobes: Remove unnecessary ‘NULL’ values from correct_ret_addr

The 'correct_ret_addr' pointer is always set in the later code, no need
to initialize it at definition time.

Link: https://lore.kernel.org/all/[e-mail]/

Signed-off-by: Li zeming <[e-mail]>
Acked-by: Masami Hiramatsu (Google) <[e-mail]>
Signed-off-by: Masami Hiramatsu (Google) <[e-mail]>

kernel/kprobes.c

···
 unsigned long __kretprobe_trampoline_handler(struct pt_regs *regs,
 					     void *frame_pointer)
 {
-	kprobe_opcode_t *correct_ret_addr = NULL;
 	struct kretprobe_instance *ri = NULL;
 	struct llist_node *first, *node = NULL;
+	kprobe_opcode_t *correct_ret_addr;
 	struct kretprobe *rp;
 
 	/* Find correct address and all nodes for this frame. */