testsuite: depmod: add module dependency outside cyclic chain

testsuite: depmod: add module dependency outside cyclic chain

Check that depmod do not report modules outside cyclic chain

Two modules f and g are added which do not have any dependency.
modules a and b are made dependent on f and g.

Here is the output of loop dependency check test after adding this
patch:

TESTSUITE: ERR: wrong:
depmod: ERROR: Found 7 modules in dependency cycles!
depmod: ERROR: Cycle detected: mod_loop_d -> mod_loop_e -> mod_loop_d
depmod: ERROR: Cycle detected: mod_loop_b -> mod_loop_c -> mod_loop_a -> mod_loop_b
depmod: ERROR: Cycle detected: mod_loop_b -> mod_loop_c -> mod_loop_a -> mod_loop_g
depmod: ERROR: Cycle detected: mod_loop_b -> mod_loop_c -> mod_loop_a -> mod_loop_f

Buffer overflow occurs in the loop when last two lines are printed.
43 bytes buffer is allocated and 53 bytes are used.

Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>