MIPS: oprofile: Fix backtrace on 64-bit kernel

Fix incorrect cast that always results in wrong address for the new
frame on 64-bit kernels.
Signed-off-by: Aaro Koskinen <aaro.koskinen@nsn.com>
Cc: stable@vger.kernel.org
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/8110/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/oprofile/backtrace.c

@@ -92,7 +92,7 @@ static inline int unwind_user_frame(struct stackframe *old_frame,
 				/* This marks the end of the previous function,
 				   which means we overran. */
 				break;
-			stack_size = (unsigned) stack_adjustment;
+			stack_size = (unsigned long) stack_adjustment;
 		} else if (is_ra_save_ins(&ip)) {
 			int ra_slot = ip.i_format.simmediate;
 			if (ra_slot < 0)