Rename sc5xx and SC59X_64

[pamolloy]

Likely all of the sc5xx symbols should be renamed to adsp-sc or similar and we need to come up with a better way to distinguish between the 32-bit and 64-bit SC59x, or perhaps we don't need to distinguish them at all.

$ rg --files-with-matches -i sc5xx | wc -l
66
$ rg --files-with-matches -i SC59X_64 | wc -l
23

• [RFC] Naming convention for Analog Devices ADSP SoC support