ci: Fix ace30_ptl test platform identifier

`intel_adsp/ace30_ptl` was renamed to `intel_adsp/ace30/ptl` in the
upstream Zephyr.

Signed-off-by: Stephanos Ioannidis <[email protected]>

Author: stephanosio

.github/workflows/ci.yml

@@ -1705,7 +1705,7 @@ jobs:
                 PLATFORM_ARGS+="-p intel_adsp/ace15_mtpm "
                 ;;
               xtensa-intel_ace30_ptl_zephyr-elf)
-                PLATFORM_ARGS+="-p intel_adsp/ace30_ptl "
+                PLATFORM_ARGS+="-p intel_adsp/ace30/ptl "
                 ;;
               xtensa-intel_tgl_adsp_zephyr-elf)
                 PLATFORM_ARGS+="-p intel_adsp/cavs25 "