s/hidl_/hal_/ for hidl_implementation_test

In preparation for it including AIDL things.

Bug: 145920591
Test: TH
Change-Id: I3cf87432e25c5993bf6b03ca3e22cdd2d8bc54a5
diff --git a/TEST_MAPPING b/TEST_MAPPING
index ef710ca..8c7bc4b 100644
--- a/TEST_MAPPING
+++ b/TEST_MAPPING
@@ -12,7 +12,7 @@
       "name": "vts_treble_vintf_vendor_test"
     },
     {
-      "name": "hidl_implementation_test"
+      "name": "hal_implementation_test"
     }
   ]
 }