sscall: Add upsampling in the RX path
sscall: Add upsampling in the RX path

This code could be merged into a single function, however,
in the future we'll be doing specific optimizations in the
downsampling/upsampling paths so it makes sense to leave
them separate for now.

Signed-off-by: Dimitris Papastamos <a91262282f71bb8488398dcc9202f777d0206664@opensource.wolfsonmicro.com>

Drakevr/sscall,Drakevr/sscall