tests: make ipcs limit calculations work when numbers are large

Test suite  failed when I ran it with kernel 3.16.  Error is the
following.

tests/ts/ipcs/limits2: line 31: [: 18446744073692774399: integer expression expected

Reference: http://lkml.iu.edu/hypermail/linux/kernel/1406.0/01869.html
Signed-off-by: Sami Kerola <kerolasa@iki.fi>

tests/ts/ipcs/limits2

@@ -28,7 +28,8 @@ ts_check_prog "bc"
 . $TS_SELF/functions.sh
 
 # TODO https://github.com/karelzak/util-linux/issues/51
-if [ $(</proc/sys/kernel/shmall) -ge $(bc <<<"2^64 / $PAGE_SIZE") ]; then
+SHMALL=$(</proc/sys/kernel/shmall)
+if [ $(bc <<<"2^64 / $PAGE_SIZE < $SHMALL") -ne 1 ]; then
 	TS_KNOWN_FAIL="yes"
 fi