Calculate the initial condition using only real numbers

The other recursion coefficients were already all using only real
number types, but the initial condition was forgotten. This has worked
thus far, but a change in the upcoming Julia v1.9 (presumably
JuliaLang/julia#47255) broke the exact correspondance between real
inputs and real-axis complex inputs for the spherical normalization.

Specifically, on Julia 1.8:
```julia
julia> r = inv(sqrt(4convert(Float64, π)))
0.28209479177387814

julia> r - real(inv(sqrt(4convert(ComplexF64, π))))
0.0
```
while with Julia 1.9:
```julia
julia> r = inv(sqrt(4convert(Float64, π)))
0.28209479177387814

julia> r - real(inv(sqrt(4convert(ComplexF64, π))))
-5.551115123125783e-17
```

The simple change that allows the tests to pass again is to just ask
for the initial condition to be calculated in the appropriate real
number type.

Author: jmert

LICENSE.md

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2017–2021: Justin Willmert
+Copyright (c) 2017–2022: Justin Willmert
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

Project.toml

@@ -1,7 +1,7 @@
 name = "AssociatedLegendrePolynomials"
 uuid = "2119f1ac-fb78-50f5-8cc0-dda848ebdb19"
 authors = ["Justin Willmert <justin@willmert.me>"]
-version = "1.0.0"
+version = "1.0.1"
 
 [compat]
 julia = "1.2"

src/calculation.jl

@@ -137,7 +137,7 @@ _fma(x, y, z) = Base.fma(x, y, z)
         y¹[ii] = sqrt(y²[ii])
     end
 
-    fill!(pm, initcond(norm, T))
+    fill!(pm, initcond(norm, real(T)))
     for m in 0:mmax
         @simd for ii in I
             if N == 2