[webgpu] support intel subgroup matrix on matmul_nbits

[xhcao]

The patch enables intel subgroup matrix on matmul_bits operator, and temporarily supports it on vulkan backend and xe-2lpg arch, we will extend the functions on more subgroup matrix configs and platforms.

Description

Motivation and Context

[xhcao]

1. The subgroup matrix feature is very relevant with hardware vendors and their architectures, they have different subgroup matrix configs, and different vendors and architectures have the different best subgroup config,
   optimizing the algorithm on one hardware will easily hurt others hardwares, so we generate code separately for different vendors in the early stages of development.
2. The PR currently only supports intel xe-2lpg architecture on vulkan, and the subgroup matrix config is f16(816) x f16(1616) = f32(8*16), we will extend the features when the dawn enables more configs.
3. The current performance on intel xe-2lpg architecture is ~20% slower than dp4a, and ~10% faster than non-dp4a.

@jchen10 @daijh PTAL, thanks.

[xhcao]

Currently, the subgroup matrix config (UINT8(832) x UINT8(328) = UINT32(8*8)) is implementing in the dawn, which the expected result may be better than dp4a.

[fs-eire]

is this feature always available in all platforms? (win/linux/mac/wasm)