Build: Replace system/lib with vendor/lib

As path of the library changed to vendor specific library path,
replacing path to reflect that.

CRs-fixed: 459125

Change-Id: I59381f6a5545401ba5f9848595d402c5435260cd
diff --git a/system.prop b/system.prop
index 81adb32..321be8b 100755
--- a/system.prop
+++ b/system.prop
@@ -4,7 +4,7 @@
 
 # Use reference RIL for initial bringup
 #rild.libpath=/system/lib/libreference-ril.so
-rild.libpath=/system/lib/libril-qc-qmi-1.so
+rild.libpath=/vendor/lib/libril-qc-qmi-1.so
 rild.libargs=-d /dev/smd0
 persist.rild.nitz_plmn=
 persist.rild.nitz_long_ons_0=