Since now depmod fails when there are module loops, let's at least give
better error messages, printing the loops we found. Since we may have
more than 1 loop, just printing the modules that are in loop is not
very clear.
Assuming as an example 2 independent loops, this is how the new messages
compare to the old ones:
Before:
depmod: ERROR: Found 5 modules in dependency cycles!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleE.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleB.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleC.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleD.ko in dependency cycle!
depmod: ERROR: /tmp/test-kmod//lib/modules/3.14.4-1-ARCH/kernel/moduleA.ko in dependency cycle!
After:
depmod: ERROR: Found 5 modules in dependency cycles!
depmod: ERROR: Cycle detected: moduleE -> moduleD -> moduleE
depmod: ERROR: Cycle detected: moduleB -> moduleC -> moduleA -> moduleB