Description of problem:
kdump.conf supports dracut_args for passing additional dracut options. It may be especially useful if we want to customize the dump target more than it is normally possible, then we can add the --mount option directly to dracut_args.
However, when doing something like 'dracut_args --mount "device mountpoint filesystem opts"', then restarting kdump service, inspecting lsinitrd shows that the --mount option is added incorrectly with the space character at the beginning of actual --mount argument. That seems to break parsing of the mount option that does not expect it to begin with a space.

Version-Release number of selected component (if applicable):
kexec-tools-2.0.17-10

How reproducible:
always

Steps to Reproduce:
1. open /etc/kdump.conf
2. remove all standard target device lines
3. add 'dracut_args --mount "device mountpoint filesystem opts"' where device, mountpoint, etc are configuration of the dump target. You could instead add any other dracut command line option where it's argument requires spaces and must be quoted.
4. save the file and restart the kdump service
5. Inspect image via appropriate lsinitrd call.

Actual results:
The image shows dracut command with --mount option that has a quoted argument containing space at the beginning, also kdump itself does not work

Expected results:
The output of lsinitrd shouldn't indicate that there is any space at the beginning of quoted argument to --mount, and dumping should save vmcore to correct location.

Additional info:
I do not have direct console access and didn't really see the output of kdump initrd, however I know that it does not produce any vmcores in /var/crash, even though everything should be correct. I've also read the code especially of /bin/mkdumprd, and it seems that the current logic in add_dracut_arg will really add space at the beginning of quoted arguments. That breaks parsing because when the kdump-lib.sh splits the --mount option argument to get device or other mountpoint info, it uses cut and cut does not trim leading spaces. So I assume it causes the problem.