ftest: Fix tst_brkm() usage.

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
Make use of ARRAY_SIZE()

Created with coccinelle patch:

@@
type T;
T[] E;
@@
- (sizeof(E)/sizeof(*E))
+ ARRAY_SIZE(E)

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
Remove returns that follows tst_exit()

Removes dead code that is never executed.

Created with coccinelle patch:

@@
expression E;
@@
tst_exit();
-return E;

Signed-off-by: Cyril Hrubis <chrubis@suse.cz>