feat: add compatibility support for QNX Neutrino

[xi-guo-0]

Based on #149

Changes

This pull request adds support for QNX in the ICD loader by making the following changes:

• Platform Definition

  • Added __QNXNTO__ to icd_platform.h to properly define platform-specific path separators and directory symbols.

• Directory Enumeration Fix

  • QNX requires a different way to access d_type in directory entries. Adjusted icd_linux.c to use _DEXTRA_FIRST(dirEntry)->d_type when compiling for QNX.

• Environment Variable Handling

  • Updated icd_linux_envvars.c to treat QNX like macOS, as QNX does not have a secure_getenv implementation.

Testing

These changes have been tested on Qualcomm SA8155P and SA8295P platforms:

Platform	OS Version
SA8155P	QNX 7.0, Android
SA8295P	QNX 7.1, Android

QNX 7.0.0 _DEXTRA_FIRST reference
QNX 7.1 _DEXTRA_FIRST reference

[CLAassistant]

All committers have signed the CLA.

[bashbaug]

LGTM. I don't have an easy way to test these changes, but they shouldn't break any of our existing configs.

The CI failure is unrelated to your changes. Thanks!