Change TWRP nano TERM env variable from pcansi to bg1.25

pcansi TERM has always had some display and/or scrolling (up, down, left or right) issues in nano on TWRP's embedded Terminal.
Most frequently seen is misaligned/displaced text on long lines and files, either initially or once scrolled through.
bg1.25 seems to be the most compatible TERM for all devices currently.

Change-Id: If00a8352ca3576085f69c12dffb5b21637c7b21c
diff --git a/etc/init/nano.rc b/etc/init/nano.rc
index f57f656..daf8215 100644
--- a/etc/init/nano.rc
+++ b/etc/init/nano.rc
@@ -1,3 +1,3 @@
 on fs
     export TERMINFO /system/etc/terminfo
-    export TERM pcansi
+    export TERM bg1.25