Fix process to disable stock recovery flashing

/system/etc/install-recovery.sh no longer exists on AOSP devices
so we will stop checking for it.

Change-Id: I9074dfc443371a27b909faa8f66998683cfb6171
diff --git a/twrp.cpp b/twrp.cpp
index 2849af7..a633bec 100644
--- a/twrp.cpp
+++ b/twrp.cpp
@@ -329,7 +329,7 @@
 	// Check for su to see if the device is rooted or not
 	if (PartitionManager.Mount_By_Path("/system", false)) {
 		// Disable flashing of stock recovery
-		if (TWFunc::Path_Exists("/system/recovery-from-boot.p") && TWFunc::Path_Exists("/system/etc/install-recovery.sh")) {
+		if (TWFunc::Path_Exists("/system/recovery-from-boot.p")) {
 			rename("/system/recovery-from-boot.p", "/system/recovery-from-boot.bak");
 			gui_print("Renamed stock recovery file in /system to prevent\nthe stock ROM from replacing TWRP.\n");
 		}