Linux 6.2 compat: add check for kernel_neon_* availability

This patch adds check for kernel_neon_* symbols on arm and arm64
platforms to address the following issues:

1. Linux 6.2+ on arm64 has exported them with EXPORT_SYMBOL_GPL, so license compatibility must be checked before use.
2. On both arm and arm64, the definitions of these symbols are guarded by CONFIG_KERNEL_MODE_NEON, but their declarations are still present. Checking in configuration phase only leads to MODPOST errors (undefined references).

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Shengqi Chen <harry-chen@outlook.com>
Closes #15711
Closes #14555
Closes: #15401