Uniform intrinsic filename

[HanKuanChen]

Hi,
I notice that intrinsic filename is in a chaos status.
V extension uses riscv_vector.h and b extension uses rvintrin.h.
Maybe we can separate each intrinsic into an independent file, and users can include what they really need instead of all intrinsics.
(e.g. to use v, b and p extension, they should include riscv_v_intrinsic.h, riscv_b_intrinsic.h and riscv_p_intrinsic.h respectively)
If users want to use all intrinsics, they can include riscv_intrinsic.h.
Any idea?

[jim-wilson]

The B extension rvintrin.h file can't be upstreamed to FSF GCC due to lack of copyright assignments. It should be ignored.

The B extension plan was to have a single header file for all of the intrinsics, but given the size of the V intrinsic header file, that seems unwise. We should have separate files for each extension, and maybe a file that combines them all. Your suggestion sounds reasonable to me.

[zakk0610]

Good idea.
IMO, V intrinsic header is too big, so I prefer to have separate header for each extension.