[Clang][RISCV] Bump rvv intrinsics version to v0.11

The LLVM now supports v0.11 of the RVV intrinsics. Users can use the macro
`riscv_v_intrinsic` to distinguish what kind of intrinsics is supported in
the compiler.

Please refer to tag descriptions under

https://github.com/riscv-non-isa/rvv-intrinsic-doc/tags

Reviewed By: kito-cheng, asb

Differential Revision: https://reviews.llvm.org/D143051