Dreport: Add Kernel Command Line Info

Add functionality to collect kernel command line
information as part of the debug data collection
process. The new plugin retrieves data from
/proc/cmdline, which contains the kernel parameters
passed during boot.

Including this information in debug reports will
enhance troubleshooting capabilities for system
boot and configuration issues in OpenBMC-based
systems. It provides a snapshot of the kernel's
runtime parameters, which can help identify
misconfigurations or diagnose boot-related
problems.

Tested on qemuarm platform.

'''
Kernel cmdline: console=ttyAMA0 root=/dev/vda rw
Enables serial console debugging
Specifies root filesystem location
Mounts root in read-write mode

[1] busctl call xyz.openbmc_project.Dump.Manager /xyz/openbmc_project/dump/bmc xyz.openbmc_project.Dump.Create CreateDump a{sv} 1 "i" i 1234

tar -xvf obmcdump_1_1742903558.tar.xz
obmcdump_1_1742903558/
obmcdump_1_1742903558/summary.log
...
obmcdump_1_1742903558/kernalcmdline.log
...

cat obmcdump_1_1742903558/kernalcmdline.log | head
console=ttyAMA0 root=/dev/vda rw
'''

Change-Id: I71177a2d3ff7b9b80ce11eb22ef01434c6ecd686
Signed-off-by: Deepak Kamat <dkamat@nvidia.com>