Type instability for output of matrix exponential

[kshyatt]

julia> using StaticArrays

julia> a = rand(ComplexF64, 4, 4);

julia> sa = SMatrix{4, 4, ComplexF64}(a);

julia> sa^0.24
4×4 Matrix{ComplexF64}:
   0.874908+0.15603im     0.151727+0.0339536im  0.237417+0.0719561im   0.138797-0.157633im
 -0.0531973-0.0687887im   0.840276+0.273785im   0.279529-0.138501im    0.180715-0.042755im
   0.289622+0.114242im   0.0899188-0.226646im    0.85235+0.186083im   0.0758456+0.333684im
   0.139949-0.0276479im  0.0144155-0.0357819im  0.106669+0.0762763im   0.927468+0.233238im

julia> sa^2.0
4×4 SMatrix{4, 4, ComplexF64, 16} with indices SOneTo(4)×SOneTo(4):
 0.229298+3.53602im  0.0232097+2.07716im    -2.15183+2.7979im   -0.885066+2.19474im
 0.629551+2.70017im   0.228516+1.496im      -1.28589+2.23414im  -0.544305+1.95987im
  1.62283+2.20926im   0.673849+1.56577im    0.228108+2.75801im   0.672545+2.01049im
 0.715161+1.50804im   0.143538+0.958167im  -0.334129+1.70432im   0.461188+1.14152im

Presumably the first one is falling back to LinearAlgebra.jl, but not having stable output here is kind of annoying.