procfs: fix /proc/statm

bda7bad6 ("procfs: speed up /proc/pid/stat, statm") broke /proc/statm
- 'text' is printed twice by mistake.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reported-by: Ulrich Drepper <drepper@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>