daisy: give proper permissions for /dev/diag

* This gives proper permission to /dev/diag node so that diag driver
  can load successfully

* Logs spam with error '-13' which basically translates to access denied/invalid permission.

* Fix this by giving system read and write access.

Before in log:
Diag_Lib:  Diag_LSM_Init: Failed to open handle to diag driver, error = 13

rootdir/etc/init.daisy.rc

@@ -25,6 +25,10 @@
 # ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
 
+on init
+    # Change permissions for /dev/diag
+    chmod 0666 /dev/diag
+
 on boot
     # add for goodix
     chown system system /dev/goodix_fp