Fixed PTS: TC_GATT_SR_GAR_BI_01_C failure

When the GATT Read Request has bad handle parameters, returns the
GATT_INVALID_HANDLE error code instead of GATT_INVALID_PDU.

Bug: 79340029
Test: Rerun PTS
Change-Id: I9de576076d7f7aece0831ef57b01c07a24209010
diff --git a/stack/gatt/gatt_sr.cc b/stack/gatt/gatt_sr.cc
index d71b60d..04eb8c5 100644
--- a/stack/gatt/gatt_sr.cc
+++ b/stack/gatt/gatt_sr.cc
@@ -567,7 +567,7 @@
 
   if (s_hdl > e_hdl || !GATT_HANDLE_IS_VALID(s_hdl) ||
       !GATT_HANDLE_IS_VALID(e_hdl)) {
-    return GATT_INVALID_PDU;
+    return GATT_INVALID_HANDLE;
   }
 
   return GATT_SUCCESS;