sanitycheck: allow device runner board-id to differ from board id

Boards like mimxrt1060_evk are recognized by the scanner through their
USB device which has an ID, but in some cases the board may be
programmed using an external J-Link probe.  Support this by adding a
probe_id key that can be added to the yaml dictionary to override the
use of id for this purpose.

Signed-off-by: Peter Bigot <peter.bigot@nordicsemi.no>
diff --git a/scripts/sanitycheck b/scripts/sanitycheck
index 6582795..04588ef 100755
--- a/scripts/sanitycheck
+++ b/scripts/sanitycheck
@@ -731,7 +731,7 @@
 
         runner = hardware.get('runner', None)
         if runner:
-            board_id = hardware.get("id", None)
+            board_id = hardware.get("probe_id", hardware.get("id", None))
             product = hardware.get("product", None)
             command = ["west", "flash", "--skip-rebuild", "-d", self.build_dir]
             command.append("--runner")