macaw-loader-ppc crashes on PPC64 musl-gcc binaries

[RyanGlScott]

Using a powerpc64-linux-musl-gcc binary obtained from https://musl.cc/, I compiled the following simple binary:

#include <stdlib.h>

int main(void) {
    int* x = malloc(sizeof(int));
    *x = 42;
    free(x);
    return 0;
}

And then loaded it using macaw-loader-ppc. Surprisingly, this fails with:

PPCTOCLoadError (MissingTOCSection ".opd")

And indeed, the compiled binary lacks an .opd section, unlike most other PPC64 binaries. I propose that we make macaw-loader-ppc less strict here. Specifically, it it encounters a PPC64 section without an .opd section, load it using the same code paths that one would use for PPC32 binaries (but using 64 bits instead of 32 bits).