Setup Accelerate and MKL for 32-bit, MKL getrf, and Metal.jl integration

[ChrisRackauckas]

Kind of a lot in a single PR but this is what I ended up with after a flight

[codecov[bot]]

Codecov Report

Merging #361 (c3a93d9) into main (9224384) will decrease coverage by 3.88%. The diff coverage is 1.31%.

@@            Coverage Diff             @@
##             main     #361      +/-   ##
==========================================
- Coverage   73.83%   69.95%   -3.88%     
==========================================
  Files          19       20       +1     
  Lines        1353     1428      +75     
==========================================
  Hits          999      999              
- Misses        354      429      +75     

Files Changed	Coverage Δ
ext/LinearSolveMKLExt.jl	38.09% <0.00%> (-54.22%)	:arrow_down:
ext/LinearSolveMetalExt.jl	0.00% <0.00%> (ø)
src/LinearSolve.jl	97.29% <ø> (ø)
src/appleaccelerate.jl	5.06% <0.00%> (-2.21%)	:arrow_down:
src/extension_algs.jl	70.83% <100.00%> (ø)

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[christiangnrd]

Tried to run the Metal benchmark and I'm getting this error:

ERROR: MethodError: no method matching do_factorization(::MetalLUFactorization, ::Matrix{Float32}, ::Vector{Float32}, ::Vector{Float32})

[ChrisRackauckas]

You need to re-instantiate for it to bring in the extension from a PR branch.

[ViralBShah]

Why do we need MKL 32-bit?

[ChrisRackauckas]

GPU comparison, Neural ODE training, mixed precision algorithms, etc.