add support for avd emulator

[dhkwon-w]

On the AVD emulator (x86[-64] host, arm[64] guest), arm[64] binaries/modules are supported via Android's native bridge layer (e.g. libndk_translation.so). This layer provides runtime bridging/translation for the ARM ABI in the emulator, and we observe the linker path presented in /proc/self/maps as /system/bin/arm[64]/linker.

Accordingly, the following function determines the linker path by checking for the presence of libndk_translation.so and works as expected both on the AVD emulator (x86[-64] host, arm[64] guest) and on real devices. Please review. Thank you.

const char* xdl_get_linker_path(void) {
#if defined(__arm__)
  struct stat st;
  if (stat("/system/lib/libndk_translation.so", &st) == 0)
    return XDL_UTIL_LINKER_PATHNAME_ARM;
  else
#elif defined(__aarch64__)
  struct stat st;
  if (stat("/system/lib64/libndk_translation.so", &st) == 0)
    return XDL_UTIL_LINKER_PATHNAME_ARM;
  else
#endif
    return XDL_UTIL_LINKER_PATHNAME;
}