Use the SDK's mlir_compiler_config.toml for blob builds

[dk-tsi]

Since mlir-compiler ggml-org#662 (SDK 0.6.4) the compiler reads FFM_CAPI_LIB and TSI_RUNTIME_LIB from mlir_compiler_config.toml, found via platformdirs ($XDG_CONFIG_HOME/taos, ~/.config/taos, /etc/taos). The SDK ships it under //.config/taos, so blob builds failed with "FFM_CAPI_LIB has not been specified". Run create-all-kernels.sh with XDG_CONFIG_HOME pointed at the SDK when that file exists; older SDKs are unchanged.

Make sure to read the contributing guidelines before submitting a PR

---

Summary by cubic

Fixes blob builds failing with SDK 0.6.4 and newer, which read library paths from mlir_compiler_config.toml instead of bundling them.

• Runs create-all-kernels.sh with XDG_CONFIG_HOME pointed at the SDK when it ships a mlir_compiler_config.toml; older SDKs and non-SDK compiler dirs run unchanged.
• Logs whether the SDK compiler config is found or the compiler's default lookup is used.
• The variable is set only for create-all-kernels.sh so the caller's XDG config lookups are unaffected.

^{Written for commit c035648. Summary will update on new commits.}