arm64: Save esr in pt_regs

To avoid passing around an extra register everywhere, save esr in
pt_regs like the rest. For proper alignment we need to have a second
(unused) register. All the printfs have to be adjusted, since
it's now an unsigned long and not an int.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
diff --git a/arch/arm/include/asm/proc-armv/ptrace.h b/arch/arm/include/asm/proc-armv/ptrace.h
index e37ad8f..bebcaf6 100644
--- a/arch/arm/include/asm/proc-armv/ptrace.h
+++ b/arch/arm/include/asm/proc-armv/ptrace.h
@@ -21,7 +21,9 @@
  * on the stack during an exception.
  */
 struct pt_regs {
+	unsigned long unused;
 	unsigned long elr;
+	unsigned long esr;
 	unsigned long regs[31];
 };