Update deprecated ccall syntax in arpack

[musm]

No description provided.

[musm]

It seems to me that all of these should be Ref not Ptr? From https://docs.julialang.org/en/latest/manual/calling-c-and-fortran-code/#Some-Examples-of-C-Wrappers-1

Note that for this code to work correctly, result_array must be declared to be of type Ref{Cdouble} and not Ptr{Cdouble}. The memory is managed by Julia and the Ref signature alerts Julia's garbage collector to keep managing the memory for result_array while the ccall executes. If Ptr{Cdouble} were used instead, the ccall may still work, but Julia's garbage collector would not be aware that the memory declared for result_array is being used by the external C function. As a result, the code may produce a memory leak if result_array never gets freed by the garbage collector, or if the garbage collector prematurely frees result_array, the C function may end up throwing an invalid memory access exception.

[yuyichao]

Doesn't really matter when used correctly.

[musm]

part of #6080

[musm]

G2g? Maybe benchmarks?

[fredrikekre]

Didn't find any ARPACK benchmarks in the suite, but better safe than sorry
@nanosoldier runbenchmarks(ALL, vs=":master")

[musm]

Thanks

[nanosoldier]

Your benchmark job has completed - possible performance regressions were detected. A full report can be found here. cc @ararslan

[musm]

g2g?

[musm]

part of #6080 (ref)