build initramfs: unclear _mpargs in instmods()

build initramfs: unclear _mpargs in instmods()

The local variable _mpargs in function instmods() in file dracut-functions
looks peculiar.  The documentation is non-existent, but still ...

First, $_mpargs is not passed to modprobe via for_each_kmod_dep.
This is strange because my guess is that "_mpargs" means
"extra arguments for modprobe".

Second, the leading "--" will be lopped when a leading pathname
is stripped via
	_mod=${_mod##*/}
It seems to me that a leading "--" should inhibit modification.

Here's the corresponding patch to current HEAD (from dracut-013.)