Add RVV qs8/qu8 vhswish kernels, configs, and tests.

[oliIMG]

[KaustubhIMG]

@fbarchard @dsharlet @bhbruce @keeranroth, If you have time, please help review this PR.

[keeranroth]

@fbarchard @dsharlet @bhbruce @keeranroth, If you have time, please help review this PR.

@oliIMG @KaustubhIMG happy to give a review, but I'm not sure what operation this is. Can you add a description as to what operation vhswish is? Ideally a comment in the code

[ken-unger]

This PR is now obsolete and can be closed as there is no longer a qs8/qu8-vhswish