boards: xtensa: Align testcase tags for intel_adsp boards

Aligns intel_adsp boards to be consistent about which testcase tags to
ignore or apply. This reduces the number of tests for intel_adsp_cavs15
because we now ignore networking and Bluetooth tests.  It increases the
number of tests for intel_adsp_cavs20 because we're no longer limited to
only kernel and sof tests.

intel_adsp_cavs18 and intel_adsp_cavs25 already had these tags and don't
need to be modified.

Signed-off-by: Maureen Helm <[email protected]>

Author: MaureenHelm

boards/xtensa/intel_adsp_cavs15/intel_adsp_cavs15.yaml

@@ -4,3 +4,7 @@ type: mcu
 arch: xtensa
 toolchain:
   - zephyr
+testing:
+  ignore_tags:
+     - net
+     - bluetooth

boards/xtensa/intel_adsp_cavs20/intel_adsp_cavs20.yaml

@@ -5,6 +5,6 @@ arch: xtensa
 toolchain:
   - zephyr
 testing:
-  only_tags:
-     - kernel
-     - sof
+  ignore_tags:
+     - net
+     - bluetooth