samples: sensor: set integration_platforms to frdm_k64f

Set integration_platforms on these samples to just frdm_k64f.
This should be sufficient to make sure these tests build.

Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
diff --git a/samples/sensor/sensor_shell/sample.yaml b/samples/sensor/sensor_shell/sample.yaml
index d721b56..7b194f4 100644
--- a/samples/sensor/sensor_shell/sample.yaml
+++ b/samples/sensor/sensor_shell/sample.yaml
@@ -2,6 +2,8 @@
   name: Shell Sensor Module Sample
 tests:
   sample.sensor.shell:
+    integration_platforms:
+      - frdm_k64f
     filter: ( CONFIG_UART_CONSOLE and CONFIG_SERIAL_SUPPORT_INTERRUPT )
     tags: shell
     harness: keyboard
diff --git a/samples/sensor/thermometer/sample.yaml b/samples/sensor/thermometer/sample.yaml
index 121cdc1..1b8ba09 100644
--- a/samples/sensor/thermometer/sample.yaml
+++ b/samples/sensor/thermometer/sample.yaml
@@ -4,3 +4,5 @@
   sample.sensor.thermometer:
     tags: sensors
     harness: sensor
+    integration_platforms:
+      - frdm_k64f