proc: Remove empty line in /proc/self/status

proc: Remove empty line in /proc/self/status

If CONFIG_SECCOMP=n, /proc/self/status includes an empty line. This causes
the iotop application to bail out with an error message.

File "/usr/local/lib64/python2.7/site-packages/iotop/data.py", line 196,
	in parse_proc_pid_status
key, value = line.split(':\t', 1)
ValueError: need more than 1 value to unpack

The problem is seen in v4.9.y but not upstream because commit af884cd4a5ae6
("proc: report no_new_privs state") has not been backported to v4.9.y.
The backport of commit fae1fa0fc6cc ("proc: Provide details on speculation
flaw mitigations") tried to address the resulting differences but was
wrong, introducing the problem.

Fixes: 51ef9af2a35b ("proc: Provide details on speculation flaw mitigations")
Cc: Kees Cook <keescook@chromium.org>
Cc: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Kees Cook <keescook@chromium.org>