depmod: ignore related modules in depmod_report_cycles

depmod: ignore related modules in depmod_report_cycles

Only print actual cyclic dependencies. Print count of all the modules
in cyclic dependency at the end of the function so that dependent
modules which are not in cyclic chain can be ignored.

Printing dependent modules which are not in cyclic chain causes buffer
overflow as m->modnamesz is not included in buffer size calculations
(loop == m is never true). This buffer overflow causes kmod to crash.

Update depmod test to reflect the change as well.

Reported-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com>