ptrace: Fix r13 register value retrieval.

It is intended to obtain the value stored in the r13
register. However, due to a misplaced "&" operator, it
inadvertently retrieves the memory address associated
with the r13 register.

Signed-off-by: Luis Silva <luis.m.silva99@hotmail.com>

Author: luismgsilva

arch/arc/kernel/ptrace.c

@@ -69,7 +69,7 @@ static int genregs_get(struct task_struct *target,
 	membuf_store(&to, cregs->r15);
 	membuf_store(&to, cregs->r14);
 #ifdef CONFIG_ISA_ARCV3
-	membuf_store(&to, &ptregs->r13);
+	membuf_store(&to, ptregs->r13);
 #else
 	membuf_store(&to, cregs->r13);
 #endif