rmnet_shs: RPS mask overridden issue

Fixes issue when user manually reduces configured cores for network
stack processing.

CRs-Fixed: 2321632
Acked-by: Mahadevan Appadurai <mappadur@qti.qualcomm.com>
Signed-off-by: Subash Abhinov Kasiviswanathan <subashab@codeaurora.org>