selftests: do not require bash to run netsocktests testcase

selftests: do not require bash to run netsocktests testcase

BugLink: http://bugs.launchpad.net/bugs/1658091
commit 3659f98b5375d195f1870c3e508fe51e52206839 upstream.

Nothing in this minimal script seems to require bash. We often run these
tests on embedded devices where the only shell available is the busybox
ash. Use sh instead.

Signed-off-by: Rolf Eike Beer <eb@emlix.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>