drivers: net: rmnet: task boost

Supports scheduler boost for tasks sending packets to rmnet when
uplink data rate reaches threshold to help with task CPU migration.

Change-Id: Ib37d9184ea700a0bae428447c35bd1b96ebe80bd
Acked-by: Weiyi Chen <weiyic@qti.qualcomm.com>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>