In many cases, it's a common practice to use the name of the
domain type of a process or the type of the usage category
instead of using ambiguous terms like sys, system, etc.
Update the property name with net. prefix for better naming to
fit the usage of the system property.
Bug: 170917042
Test: 1. m -j10
2. Check if /proc/sys/net/ipv4/tcp_default_init_rwnd is
updated as expected
Change-Id: I0267880d62cc504a419827732780d2db97b2dfef
7396fed802