[Build] Improve build performance by increasing the make parallel jobs

[xumia]

Why I did it

[Build] Improve build performance by increasing the make parallel jobs
The average CPU is around 16.2% as below in the chart.

How I did it

The Paralle Jobs (-j) is set to 200% of the number of the CPU.
The Load Average (-l) is set to 80% of the number of the CPU.
See https://www.gnu.org/software/make/manual/make.html#Parallel

If the average CPU is exceeded 80% and there are running jobs, then no new jobs will be triggered.
The average CPU can be retrieved by the following commands:

$ uptime
 05:02:54 up 49 days,  4:52,  0 users,  load average: 5.45, 5.49, 3.79

$ cat /proc/loadavg
5.50 5.50 3.80 12/729 28126

How to verify it

Which release branch to backport (provide reason below if selected)

• 201811
• 201911
• 202006
• 202012
• 202106
• 202111

Description for the changelog

Link to config_db schema for YANG module changes

A picture of a cute animal (not mandatory but encouraged)