sbc: Fix for overflow bug in SBC quantization code
sbc: Fix for overflow bug in SBC quantization code

The result of multiplication does not always fit into 32-bits. Using 64-bit
calculations helps to avoid overflows and sound quality problems in encoded
audio. Overflows are more likely to show up when using high values for
bitpool setting.

pstglia/external-bluetooth-sbc,pstglia/external-bluetooth-sbc